Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary: A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only precondition is that PBM verification is reachable. On the server side this is reached from OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected messages, and on the client side from CMP response validation against a malicious or on-path (MITM) server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled memory write, and no path to code execution. CMP is a specialized feature that an application must explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.

suse_linux SUSE-SU-2026:4032-1: SUSE SLES15 : Security update for openssl-3 (Important) (SUSE-SU-2026:4032-1)

suse_linux SUSE-SU-2026:4039-1: SUSE SLED15 / SLES15 : Security update for openssl-3 (Important) (SUSE-SU-2026:4039-1)

suse_linux SUSE-SU-2026:4038-1: SUSE SLES15 : Security update for openssl-3-livepatches (Important) (SUSE-SU-2026:4038-1)

suse_linux SUSE-SU-2026:4040-1: SUSE SLES15 : Security update for openssl-3-livepatches (Important) (SUSE-SU-2026:4040-1)

The remote RockyLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RLSA-2026:67165 advisory.

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)

    * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)

    * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)

    * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)

    * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)

    * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)

    * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)

    * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)

    * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

    Bug Fix(es) and Enhancement(s):

    * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [Rocky Linux 9.8.z] (JIRA:Rocky     Linux-232828)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote AlmaLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:67154 advisory.

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)
      * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)
      * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)
      * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)
      * openssl: RPK server signature algorithm selection can dereference a missing certificate     (CVE-2026-14457)
      * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)
      * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)
      * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)
      * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)


    Bug Fix(es) and Enhancement(s):

      * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 10.2.z]     (JIRA:AlmaLinux-212362)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:67165 advisory.

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)
      * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)
      * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)
      * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)
      * openssl: RPK server signature algorithm selection can dereference a missing certificate     (CVE-2026-14457)
      * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)
      * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)
      * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)
      * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)


    Bug Fix(es) and Enhancement(s):

      * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 9.8.z]     (JIRA:AlmaLinux-232828)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote RockyLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the RLSA-2026:67154 advisory.

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)

    * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)

    * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)

    * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)

    * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)

    * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)

    * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)

    * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)

    * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

    Bug Fix(es) and Enhancement(s):

    * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [Rocky Linux 10.2.z] (JIRA:Rocky     Linux-212362)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2136 advisory.

    Issue summary: In a server or client configuration with RFC7250 Raw Public Keys (RPKs)enabled, and only     the private key (with no associated certificate) configured locally,a NULL pointer dereference may occur     when the remote peer solicits raw public keys andalso sends the typically omitted     signature_algorithms_cert TLS extension.

    Impact summary: The impact is limited to a possible Denial of Service as a result ofan application abort,     no data disclosure or remote command execution are possible.

    CWE: CWE-476: NULL Pointer Dereference

    Description: While a passing comment in sample code in the documentation suggeststhat key-only RPK     configurations are supported, the best-practice RPK configurationis to always configure a corresponding     certificate (possibly self-signed orsigned by any convenient CA).

    When the private key is configured along with a matching certificate, thesignature_algorithms_cert     extension is handled reliably even without thefix, and peer clients or servers that don't support raw     public keys may beable to complete a TLS connection by pinning or verifying the correspondingcertificate     or its public key.

    Deployments that prefer to configure just a private key with no certificateneed to upgrade to an updated     release as noted below.

    FIPS impact: no

    No FIPS modules are affected by this issue, as the SSL protocol implementationis outside the OpenSSL FIPS     module boundary. (CVE-2026-14457)

    Issue summary: QUIC server may double free QRX (QUIC record layer RX) objectwhen channel creation fails     for initial packet.

    Impact summary: Double free leads to heap corruption, which typically results intermination of QUIC server     process, leading to Denial of Service. There is sofar no evidence that this double free is exploitable for     remote code execution,thus it is considered highly improbable.

    CWE: CWE-415: Double Free

    Description: In order to validate initial packet, OpenSSL QUIC stack defaultpacket handler     (port_default_packet_handler()) creates a so-called QRX object.If the initial packet validates     successfully with QRX object, the default packethandler proceeds to channel (connection object) creation.
    The QRX object usedfor packet validation is passed to port_bind_channel(), so it becomes part ofthe newly     created connection. If port_bind_channel() fails, then it also freesthe QRX object. Once     port_bind_channel() returns, the port_default_packet_handler()detects the failure and proceeds to the     error branch, where the same QRX object isfreed for the second time.

    The failure in port_bind_channel() function can be induced with a relativelylow effort by a malformed (non     RFC 9000 compliant) INITIAL packet. If the packetcarries DCID (destination connection ID) which is shorter     than 8 bytes, thenport_bind_channel() jumps to the error path after ossl_quic_lcidm_enrol_odcid()detects     that the DCID has invalid length.

    FIPS impact: noThe FIPS module is not affected, as the QUIC implementation is outside ofthe OpenSSL FIPS     module boundary. (CVE-2026-18798)

    Issue summary: Receiving a DTLS record for a future epoch while a handshakeis in progress causes OpenSSL     to buffer far more memory than the recorditself requires.

    Impact summary: A peer can use a small amount of network traffic to make anOpenSSL DTLS endpoint retain a     disproportionately large amount of memory,which may lead to a Denial of Service.

    CWE: CWE-405: Asymmetric Resource Consumption (Amplification)

    Description: While a DTLS handshake is in progress, a peer may legitimatelyhave already moved on to the     next epoch (for example, having sent itsChangeCipherSpec and Finished messages) before the local endpoint     hasprocessed the same transition, typically because of reordering on theunderlying UDP transport. OpenSSL     buffers such early records so that theycan be processed once the local endpoint catches up.

    Buffering a record currently retains the entire read buffer it arrived in,which is sized to hold the     largest possible DTLS record (around 16kilobytes), rather than just the bytes that make up the record     itself. Upto 100 such records may be buffered per connection. As a result, a peerthat sends a stream of     small forged records claiming to belong to the nextepoch can cause an OpenSSL DTLS endpoint to retain     around 1.7 megabytes ofmemory, despite sending only a small fraction of that amount of data overthe     network.

    An attacker therefore gains a memory amplification factor of around 1200,and can multiply the effect     across as many associations as it is able toopen, making this a remote memory exhaustion Denial of Service     risk forDTLS servers. Since the memory retained per connection remains bounded,and any limit an     application already places on the number of concurrentassociations also bounds the total exposure, this     issue has been assessedas Low severity.

    FIPS impact: no

    No FIPS modules are affected by this issue as the affected code is outsidethe OpenSSL FIPS module     boundary.

    OpenSSL 4.0, 3.6, 3.5, 3.4, 3.0, 1.1.1 and 1.0.2 are vulnerable to thisissue.

    OpenSSL 4.0 users should upgrade to OpenSSL 4.0.2.OpenSSL 3.6 users should upgrade to OpenSSL     3.6.4.OpenSSL 3.5 users should upgrade to OpenSSL 3.5.8.OpenSSL 3.4 users should upgrade to OpenSSL     3.4.7.OpenSSL 3.0 users should upgrade to OpenSSL 3.0.22.

    Premium support customers only:OpenSSL 1.1.1 users should upgrade to OpenSSL 1.1.1ziOpenSSL 1.0.2 users     should upgrade to OpenSSL 1.0.2zr

    This issue was reported on 18 May 2026 by Amazon Web Services.The fix has been developed by Matt Caswell.

    -- cut (non-publishing metadata for internal use) --Reported by: Amazon Web ServicesFixed by: Matt Caswell     (CVE-2026-54874)

    Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer basedon querying the unwrapped     key size, but the AES-WRAP-PAD unwrap primitivecan write and cleanse more bytes than that query reports,     causing an 8-byteout-of-bounds heap write.

    Impact summary: An attacker who supplies a crafted CMS message can trigger adeterministic 8-byte out-of-     bounds heap write when the victim decrypts itwith CMS_decrypt(), corrupting the heap and typically     resulting in a Denialof Service.

    CWE: CWE-787: Out-of-bounds Write

    Description: The key-wrap OID is potentially attacker-controlled on the wire.CMS unwrapping allows both     id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers.An attacker can take a legitimate message and change a     single OID byte toselect the padded variant while leaving the message otherwise valid. Sincethe unwrap key     is derived from the recipient's private operation (ECDH keyagreement or ML-KEM decapsulation), the RFC     5649 integrity check cannotpass, and the decryption fails with integrity failure.

    The write is a fixed-size (8-byte), fixed-value (zero) heap overflowimmediately past the allocation,     requires no special configuration, and isreachable from the public CMS_decrypt() function. The consequence     isa heap corruption leading to a Denial of Service. The fix in the CMS codesizes the unwrap output buffer     for the worst case so a failed unwrap cannotwrite past the allocation.

    FIPS impact: no

    As the CMS code lives outside the FIPS module boundary, no FIPSmodules are affected by this CVE.
    (CVE-2026-63072)

    Issue summary: OpenSSL CMP response validation passed an unexpected responsesender distinguished name     directly as the format string to `ERR_raise_data()`.

    Impact summary: A malicious or intercepted CMP endpoint can crash a CMP clientthat enforces an expected     sender or uses a pinned server certificate whosesubject becomes the default expected sender.

    CWE: CWE-134 (Use of Externally-Controlled Format String)

    Description: When validating a received CMP message, ossl_cmp_msg_check_update()converts the peer-supplied     sender distinguished name with X509_NAME_oneline()and passes it directly as the format argument to     ERR_raise_data(). Percentcharacters survive the conversion, so a sender DN such as CN=%s%n     reachesBIO_vsnprintf() as an attacker-controlled format string with no matching variadicarguments. This     path is only reached when the caller configures an expectedsender or pins a server certificate, which is     the normal configuration for aCMP client validating server responses.

    Since the attacker controls the format string but none of the variadicarguments, such specifiers as %s and     %n dereference or write through unrelatedstack contents and crash the client. The reliable consequence is     a denial ofservice, when the response comes from a malicious or intercepted CMP endpoint.There is no     controlled memory write, arbitrary-address read, or reliable pathto remote code execution.

    FIPS impact: no

    No FIPS modules are affected by this issue, as the CMP protocolimplementation is outside the OpenSSL FIPS     module boundary. (CVE-2026-63073)

    Issue summary: The OpenSSL Certificate Management Protocol (CMP) cachesadditional certificates     (extraCerts) sent in a CMP message, but never expungesthem (for instance if they are invalid).  If a     server reuses an OSSL_CMP_CTXfrequently, this cache of extraCerts may grow unboundedly, and a     maliciousclient may flood a CMP server with requests driving this growth.

    Impact summary: Users utilizing a CMP server that reuses a single OSSL_CMP_CTXfor the lifetime of a server     process may observe unbounded memory growth in theevent a malicious client repeatedly sends requests     containing unique extracertificates, which may lead to OOM conditions.

    CWE: CWE-770: Allocation of Resources Without Limits or Throttling

    Description: If a remote user sends CMP messages to a server with a list ofextraCerts and the message is     rejected, the extraCerts from the message remainsin the server contexts untrusted certificate stack.  This     exposes servers withlong lived ctx objects to Denial of Service attacks in which an attacker sendsmessages     intending to be rejected with a large list of additional certificatesrepeatedly, forcing the server to     store them indefinitely.The issue was fixed by removing the added extra certs if the message isrejected,     using the same method as when the context is configured to not docaching at all.

    FIPS impact: noAs the CMP code lives outside the FIPS module boundary, no FIPSmodules are affected by this     CVE. (CVE-2026-63074)

    Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedlysends ack-eliciting packets     while not acknowledging ACK-only responses, theQUIC stack can retain ACK-only packet metadata for the     lifetime of theconnection.

    Impact summary: A remote peer that can complete a QUIC handshake cancause connection-scoped memory growth     which may lead to Denial of Servicethrough memory exhaustion, especially with sustained traffic or many     concurrentQUIC connections.

    CWE: CWE-770: Allocation of Resources Without Limits or Throttling

    Description: When the OpenSSL QUIC stack sends an ACK-only packet,there is no requirement by the QUIC     protocol that the peer will acknowledgethat ACK-only packet (i.e. it is itself not ack-eliciting).
    However, the OpenSSLimplementation stores the metadata about the ACK frames regardless.In and of itself     that's ok, but if a malicious peer establishes a connection, andthen drives the connection such that ACK-     only packets are forced from theOpenSSL implementation peer (i.e., by sending numerous PING frames),and     then withholding any subsequent acks for ack-eliciting data, likelegitimate data, said malicious peer can     force inappropriate memory growthon the OpenSSL peer, potentially leading to a Denial of Service.

    The fix is to ensure that we account for the transmission of the ACK-onlypacket in the packet histories     high and low watermark without actually storingthe ACK-only packet metadata itself.

    FIPS impact: noThe OpenSSL FIPS module is not affected as the QUIC code isoutside the FIPS module     boundary. (CVE-2026-63075)

    Issue summary: OpenSSL CMP password based protection verification onlychecks whether the protectionAlg     parameter was not NULL and not itsASN.1 type, before treating it as a PBMParameter. A crafted message     cancontain a parameter of a different type, which is then dereferenced as aninvalid pointer.

    Impact summary: A remote, unauthenticated attacker can crash an applicationacting as a CMP server that     accepts PBM-protected messages, or a CMP clienttalking to a malicious or intercepted CMP server, resulting     in a Denial ofService.

    CWE: CWE-476: NULL Pointer Dereference

    Description: When verifying the password-based MAC protection of a CMPmessage, OpenSSL library reads the     protectionAlg algorithm parameter withX509_ALGOR_get0(), which returns both the parameter type and its     valuepointer. The value is then cast to an ASN1_STRING and treated as theexpected PBMParameter after only     checking that pointer is not NULL. Theparameter type returned by X509_ALGOR_get0() was never consulted.

    This happens during protection verification, before any MAC is computed, sono knowledge of the PBM shared     secret is required; the only precondition isthat PBM verification is reachable. On the server side this is     reached fromOSSL_CMP_SRV_process_request() for any application that stands up a CMPserver accepting PBM-     protected messages, and on the client side from CMPresponse validation against a malicious or on-path     (MITM) server. Thereliable consequence is a denial of service; there is no memory disclosure,no controlled     memory write, and no path to code execution. CMP is aspecialized feature that an application must     explicitly enable.

    FIPS impact: noAs the CMP code lives outside the FIPS module boundary, no FIPS modulesare affected by this     CVE. (CVE-2026-63076)

    Check the tag on EVP_Cipher() finalize: Poly1305 and OCB AEADs (CVE-2026-75803)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Oracle Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-671650 advisory.

    [3.5.8-1.0.1]
    - Replace upstream references [Orabug: 34340177]

    [3.5.8.openela.0.1]
    - Add OpenELA specific changes

    [1:3.5.8-1]
    - Rebase to OpenSSL 3.5.8       Resolves: RHEL-242945       Resolves: RHEL-246260       Resolves: RHEL-246284       Resolves: RHEL-246319       Resolves: RHEL-246439       Resolves: RHEL-246443       Resolves: RHEL-246447       Resolves: RHEL-246451       Resolves: RHEL-246455

    [1:3.5.5-7]
    - Backport the 'HollowByte' hardening patch       Resolves: RHEL-232828

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Oracle Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-671540 advisory.

    [3.5.8-1.0.1]
    - Replace upstream references [Orabug: 34340177]
    - Update FIPS provider name [Orabug: 35824276]

    [1:3.5.8-1]
    - Rebase to OpenSSL 3.5.8       Resolves: RHEL-242944       Resolves: RHEL-246254       Resolves: RHEL-246266       Resolves: RHEL-246306       Resolves: RHEL-246437       Resolves: RHEL-246441       Resolves: RHEL-246445       Resolves: RHEL-246449       Resolves: RHEL-246453

    [1:3.5.5-7]
    - Backport the 'HollowByte' hardening patch       Resolves: RHEL-212362

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:67165 advisory.

    OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS)     protocols, as well as a full-strength general-purpose cryptography library.

    Security Fix(es):

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)

    * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)

    * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)

    * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)

    * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)

    * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)

    * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)

    * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)

    * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

    Bug Fix(es) and Enhancement(s):

    * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [RHEL 9.8.z] (JIRA:RHEL-232828)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:67154 advisory.

    OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS)     protocols, as well as a full-strength general-purpose cryptography library.

    Security Fix(es):

    * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)

    * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)

    * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)

    * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)

    * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)

    * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)

    * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)

    * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)

    * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

    Bug Fix(es) and Enhancement(s):

    * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [RHEL 10.2.z] (JIRA:RHEL-212362)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the 9008d14d-a0af-11f1-8144-8447094a420f advisory.

    The OpenSSL poject reports:

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 13 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-6465 advisory.

    - -------------------------------------------------------------------------     Debian Security Advisory DSA-6465-1                   security@debian.org     https://www.debian.org/security/                     Salvatore Bonaccorso     August 25, 2026                       https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : openssl     CVE ID         : CVE-2026-14456 CVE-2026-14457 CVE-2026-18798 CVE-2026-54874                      CVE-2026-63072 CVE-2026-63073 CVE-2026-63074 CVE-2026-63075                      CVE-2026-63076 CVE-2026-75803     Debian Bug     : 1144615 1145172

    Multiple vulnerabilities have been discovered in OpenSSL, a Secure     Sockets Layer toolkit, which may result in denial of service.

    Additional details can be found in the upstream advisories:
    https://openssl-library.org/news/secadv/20260813.txt     https://openssl-library.org/news/secadv/20260825.txt

    For the stable distribution (trixie), these problems have been fixed in     version 3.5.7-1~deb13u2.

    We recommend that you upgrade your openssl packages.

    For the detailed security status of openssl please refer to its security     tracker page at:
    https://security-tracker.debian.org/tracker/openssl

    Further information about Debian Security Advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://www.debian.org/security/

    Mailing list: debian-security-announce@lists.debian.org

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of OpenSSL installed on the remote host is prior to 3.0.22. It is, therefore, affected by multiple vulnerabilities as referenced in the 3.0.22 advisory.

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

  - Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success     without verifying the supplied authentication tag when the operation is finalized by calling the     EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and     expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of     Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot     encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for     AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was     passed to the function. The callers of this function might believe that a successful return indicates a     valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact:
    no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms     are not FIPS approved and thus not implemented in the FIPS module. (CVE-2026-75803)

  - Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates     (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a     server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious     client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP     server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory     growth in the event a malicious client repeatedly sends requests containing unique extra certificates,     which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling     Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is     rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This     exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends     messages intending to be rejected with a large list of additional certificates repeatedly, forcing the     server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is     rejected, using the same method as when the context is configured to not do caching at all. FIPS impact:
    no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
    (CVE-2026-63074)

  - Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped     key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports,     causing an 8-byte out-of-bounds heap write. Impact summary: An attacker who supplies a crafted CMS message     can trigger a deterministic 8-byte out-of-bounds heap write when the victim decrypts it with     CMS_decrypt(), corrupting the heap and typically resulting in a Denial of Service. CWE: CWE-787: Out-of-     bounds Write Description: The key-wrap OID is potentially attacker-controlled on the wire. CMS unwrapping     allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers. An attacker can take a legitimate message and     change a single OID byte to select the padded variant while leaving the message otherwise valid. Since the     unwrap key is derived from the recipient's private operation (ECDH key agreement or ML-KEM decapsulation),     the RFC 5649 integrity check cannot pass, and the decryption fails with integrity failure. The write is a     fixed-size (8-byte), fixed-value (zero) heap overflow immediately past the allocation, requires no special     configuration, and is reachable from the public CMS_decrypt() function. The consequence is a heap     corruption leading to a Denial of Service. The fix in the CMS code sizes the unwrap output buffer for the     worst case so a failed unwrap cannot write past the allocation. FIPS impact: no As the CMS code lives     outside the FIPS module boundary, no FIPS modules are affected by this CVE. (CVE-2026-63072)

  - Issue summary: Receiving a DTLS record for a future epoch while a handshake is in progress causes OpenSSL     to buffer far more memory than the record itself requires. Impact summary: A peer can use a small amount     of network traffic to make an OpenSSL DTLS endpoint retain a disproportionately large amount of memory,     which may lead to a Denial of Service. CWE: CWE-405: Asymmetric Resource Consumption (Amplification)     Description: While a DTLS handshake is in progress, a peer may legitimately have already moved on to the     next epoch (for example, having sent its ChangeCipherSpec and Finished messages) before the local endpoint     has processed the same transition, typically because of reordering on the underlying UDP transport.
    OpenSSL buffers such early records so that they can be processed once the local endpoint catches up.
    Buffering a record currently retains the entire read buffer it arrived in, which is sized to hold the     largest possible DTLS record (around 16 kilobytes), rather than just the bytes that make up the record     itself. Up to 100 such records may be buffered per connection. As a result, a peer that sends a stream of     small forged records claiming to belong to the next epoch can cause an OpenSSL DTLS endpoint to retain     around 1.7 megabytes of memory, despite sending only a small fraction of that amount of data over the     network. An attacker therefore gains a memory amplification factor of around 1200, and can multiply the     effect across as many associations as it is able to open, making this a remote memory exhaustion Denial of     Service risk for DTLS servers. Since the memory retained per connection remains bounded, and any limit an     application already places on the number of concurrent associations also bounds the total exposure, this     issue has been assessed as Low severity. FIPS impact: no No FIPS modules are affected by this issue as the     affected code is outside the OpenSSL FIPS module boundary. OpenSSL 4.0, 3.6, 3.5, 3.4, 3.0, 1.1.1 and     1.0.2 are vulnerable to this issue. OpenSSL 4.0 users should upgrade to OpenSSL 4.0.2. OpenSSL 3.6 users     should upgrade to OpenSSL 3.6.4. OpenSSL 3.5 users should upgrade to OpenSSL 3.5.8. OpenSSL 3.4 users     should upgrade to OpenSSL 3.4.7. OpenSSL 3.0 users should upgrade to OpenSSL 3.0.22. Premium support     customers only: OpenSSL 1.1.1 users should upgrade to OpenSSL 1.1.1zi OpenSSL 1.0.2 users should upgrade     to OpenSSL 1.0.2zr This issue was reported on 18 May 2026 by Amazon Web Services. The fix has been     developed by Matt Caswell. -- cut (non-publishing metadata for internal use) -- Reported by: Amazon Web     Services Fixed by: Matt Caswell (CVE-2026-54874)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of OpenSSL installed on the remote host is prior to 3.4.7. It is, therefore, affected by multiple vulnerabilities as referenced in the 3.4.7 advisory.

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

  - Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success     without verifying the supplied authentication tag when the operation is finalized by calling the     EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and     expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of     Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot     encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for     AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was     passed to the function. The callers of this function might believe that a successful return indicates a     valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact:
    no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms     are not FIPS approved and thus not implemented in the FIPS module. (CVE-2026-75803)

  - Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets     while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the     lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause     connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially     with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without     Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no     requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself     not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames     regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives     the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by     sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like     legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer,     potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of     the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only     packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is     outside the FIPS module boundary. (CVE-2026-63075)

  - Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates     (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a     server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious     client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP     server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory     growth in the event a malicious client repeatedly sends requests containing unique extra certificates,     which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling     Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is     rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This     exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends     messages intending to be rejected with a large list of additional certificates repeatedly, forcing the     server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is     rejected, using the same method as when the context is configured to not do caching at all. FIPS impact:
    no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
    (CVE-2026-63074)

  - Issue summary: OpenSSL CMP response validation passed an unexpected response sender distinguished name     directly as the format string to `ERR_raise_data()`. Impact summary: A malicious or intercepted CMP     endpoint can crash a CMP client that enforces an expected sender or uses a pinned server certificate whose     subject becomes the default expected sender. CWE: CWE-134 (Use of Externally-Controlled Format String)     Description: When validating a received CMP message, ossl_cmp_msg_check_update() converts the peer-     supplied sender distinguished name with X509_NAME_oneline() and passes it directly as the format argument     to ERR_raise_data(). Percent characters survive the conversion, so a sender DN such as CN=%s%n reaches     BIO_vsnprintf() as an attacker-controlled format string with no matching variadic arguments. This path is     only reached when the caller configures an expected sender or pins a server certificate, which is the     normal configuration for a CMP client validating server responses. Since the attacker controls the format     string but none of the variadic arguments, such specifiers as %s and %n dereference or write through     unrelated stack contents and crash the client. The reliable consequence is a denial of service, when the     response comes from a malicious or intercepted CMP endpoint. There is no controlled memory write,     arbitrary-address read, or reliable path to remote code execution. FIPS impact: no No FIPS modules are     affected by this issue, as the CMP protocol implementation is outside the OpenSSL FIPS module boundary.
    (CVE-2026-63073)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of OpenSSL installed on the remote host is prior to 3.5.8. It is, therefore, affected by multiple vulnerabilities as referenced in the 3.5.8 advisory.

  - Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets     while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the     lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause     connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially     with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without     Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no     requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself     not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames     regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives     the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by     sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like     legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer,     potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of     the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only     packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is     outside the FIPS module boundary. (CVE-2026-63075)

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

  - Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success     without verifying the supplied authentication tag when the operation is finalized by calling the     EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and     expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of     Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot     encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for     AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was     passed to the function. The callers of this function might believe that a successful return indicates a     valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact:
    no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms     are not FIPS approved and thus not implemented in the FIPS module. (CVE-2026-75803)

  - Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates     (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a     server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious     client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP     server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory     growth in the event a malicious client repeatedly sends requests containing unique extra certificates,     which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling     Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is     rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This     exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends     messages intending to be rejected with a large list of additional certificates repeatedly, forcing the     server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is     rejected, using the same method as when the context is configured to not do caching at all. FIPS impact:
    no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
    (CVE-2026-63074)

  - Issue summary: OpenSSL CMP response validation passed an unexpected response sender distinguished name     directly as the format string to `ERR_raise_data()`. Impact summary: A malicious or intercepted CMP     endpoint can crash a CMP client that enforces an expected sender or uses a pinned server certificate whose     subject becomes the default expected sender. CWE: CWE-134 (Use of Externally-Controlled Format String)     Description: When validating a received CMP message, ossl_cmp_msg_check_update() converts the peer-     supplied sender distinguished name with X509_NAME_oneline() and passes it directly as the format argument     to ERR_raise_data(). Percent characters survive the conversion, so a sender DN such as CN=%s%n reaches     BIO_vsnprintf() as an attacker-controlled format string with no matching variadic arguments. This path is     only reached when the caller configures an expected sender or pins a server certificate, which is the     normal configuration for a CMP client validating server responses. Since the attacker controls the format     string but none of the variadic arguments, such specifiers as %s and %n dereference or write through     unrelated stack contents and crash the client. The reliable consequence is a denial of service, when the     response comes from a malicious or intercepted CMP endpoint. There is no controlled memory write,     arbitrary-address read, or reliable path to remote code execution. FIPS impact: no No FIPS modules are     affected by this issue, as the CMP protocol implementation is outside the OpenSSL FIPS module boundary.
    (CVE-2026-63073)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of OpenSSL installed on the remote host is prior to 3.6.4. It is, therefore, affected by multiple vulnerabilities as referenced in the 3.6.4 advisory.

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

  - Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success     without verifying the supplied authentication tag when the operation is finalized by calling the     EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and     expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of     Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot     encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for     AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was     passed to the function. The callers of this function might believe that a successful return indicates a     valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact:
    no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms     are not FIPS approved and thus not implemented in the FIPS module. (CVE-2026-75803)

  - Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets     while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the     lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause     connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially     with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without     Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no     requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself     not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames     regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives     the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by     sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like     legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer,     potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of     the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only     packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is     outside the FIPS module boundary. (CVE-2026-63075)

  - Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates     (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a     server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious     client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP     server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory     growth in the event a malicious client repeatedly sends requests containing unique extra certificates,     which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling     Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is     rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This     exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends     messages intending to be rejected with a large list of additional certificates repeatedly, forcing the     server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is     rejected, using the same method as when the context is configured to not do caching at all. FIPS impact:
    no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
    (CVE-2026-63074)

  - Issue summary: OpenSSL CMP response validation passed an unexpected response sender distinguished name     directly as the format string to `ERR_raise_data()`. Impact summary: A malicious or intercepted CMP     endpoint can crash a CMP client that enforces an expected sender or uses a pinned server certificate whose     subject becomes the default expected sender. CWE: CWE-134 (Use of Externally-Controlled Format String)     Description: When validating a received CMP message, ossl_cmp_msg_check_update() converts the peer-     supplied sender distinguished name with X509_NAME_oneline() and passes it directly as the format argument     to ERR_raise_data(). Percent characters survive the conversion, so a sender DN such as CN=%s%n reaches     BIO_vsnprintf() as an attacker-controlled format string with no matching variadic arguments. This path is     only reached when the caller configures an expected sender or pins a server certificate, which is the     normal configuration for a CMP client validating server responses. Since the attacker controls the format     string but none of the variadic arguments, such specifiers as %s and %n dereference or write through     unrelated stack contents and crash the client. The reliable consequence is a denial of service, when the     response comes from a malicious or intercepted CMP endpoint. There is no controlled memory write,     arbitrary-address read, or reliable path to remote code execution. FIPS impact: no No FIPS modules are     affected by this issue, as the CMP protocol implementation is outside the OpenSSL FIPS module boundary.
    (CVE-2026-63073)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of OpenSSL installed on the remote host is prior to 4.0.2. It is, therefore, affected by multiple vulnerabilities as referenced in the 4.0.2 advisory.

  - Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped     key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports,     causing an 8-byte out-of-bounds heap write. Impact summary: An attacker who supplies a crafted CMS message     can trigger a deterministic 8-byte out-of-bounds heap write when the victim decrypts it with     CMS_decrypt(), corrupting the heap and typically resulting in a Denial of Service. CWE: CWE-787: Out-of-     bounds Write Description: The key-wrap OID is potentially attacker-controlled on the wire. CMS unwrapping     allows both id-aesNNN-wrap-pad and id-aesNNN-wrap ciphers. An attacker can take a legitimate message and     change a single OID byte to select the padded variant while leaving the message otherwise valid. Since the     unwrap key is derived from the recipient's private operation (ECDH key agreement or ML-KEM decapsulation),     the RFC 5649 integrity check cannot pass, and the decryption fails with integrity failure. The write is a     fixed-size (8-byte), fixed-value (zero) heap overflow immediately past the allocation, requires no special     configuration, and is reachable from the public CMS_decrypt() function. The consequence is a heap     corruption leading to a Denial of Service. The fix in the CMS code sizes the unwrap output buffer for the     worst case so a failed unwrap cannot write past the allocation. FIPS impact: no As the CMS code lives     outside the FIPS module boundary, no FIPS modules are affected by this CVE. (CVE-2026-63072)

  - Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets     while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the     lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause     connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially     with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without     Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no     requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself     not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames     regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives     the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by     sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like     legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer,     potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of     the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only     packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is     outside the FIPS module boundary. (CVE-2026-63075)

  - Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success     without verifying the supplied authentication tag when the operation is finalized by calling the     EVP_Cipher() function. Impact summary: Applications calling EVP_Cipher() on an empty ciphertext and     expecting the call to check the AEAD tag may accept forged messages. CWE: CWE-354 (Improper Validation of     Integrity Check Value) Description: The EVP_Cipher() API call for AEAD ciphers behaves like a one shot     encryption and decryption call. It also verifies the AEAD tag after the decryption operation. However for     AES-OCB and ChaCha20-Poly1305 ciphers it skipped the AEAD tag verification when an empty ciphertext was     passed to the function. The callers of this function might believe that a successful return indicates a     valid AEAD tag for these ciphers, even when that has not truly been validated in this case. FIPS impact:
    no The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this CVE as the affected algorithms     are not FIPS approved and thus not implemented in the FIPS module. (CVE-2026-75803)

  - Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg     parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can     contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary:
    A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-     protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a     Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based     MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with     X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to     an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The     parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection     verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only     precondition is that PBM verification is reachable. On the server side this is reached from     OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected     messages, and on the client side from CMP response validation against a malicious or on-path (MITM)     server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled     memory write, and no path to code execution. CMP is a specialized feature that an application must     explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules     are affected by this CVE. (CVE-2026-63076)

  - Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates     (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a     server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious     client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP     server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory     growth in the event a malicious client repeatedly sends requests containing unique extra certificates,     which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling     Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is     rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This     exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends     messages intending to be rejected with a large list of additional certificates repeatedly, forcing the     server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is     rejected, using the same method as when the context is configured to not do caching at all. FIPS impact:
    no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE.
    (CVE-2026-63074)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
346036	RockyLinux 9 : openssl (RLSA-2026:67165)	Nessus	Rocky Linux Local Security Checks	Local	critical
345934	AlmaLinux 10 : openssl (ALSA-2026:67154)	Nessus	Alma Linux Local Security Checks	Local	critical
345932	AlmaLinux 9 : openssl (ALSA-2026:67165)	Nessus	Alma Linux Local Security Checks	Local	critical
345922	RockyLinux 10 : openssl (RLSA-2026:67154)	Nessus	Rocky Linux Local Security Checks	Local	critical
345807	Amazon Linux 2023 : openssl, openssl-devel, openssl-fips-provider-latest (ALAS2023-2026-2136)	Nessus	Amazon Linux Local Security Checks	Local	critical
345694	Oracle Linux 9 : ELSA-2026-67165-0: / openssl (ELSA-2026-671650)	Nessus	Oracle Linux Local Security Checks	Local	critical
345693	Oracle Linux 10 : ELSA-2026-67154-0: / openssl (ELSA-2026-671540)	Nessus	Oracle Linux Local Security Checks	Local	critical
345607	RHEL 9 : openssl (RHSA-2026:67165)	Nessus	Red Hat Local Security Checks	Local	critical
345599	RHEL 10 : openssl (RHSA-2026:67154)	Nessus	Red Hat Local Security Checks	Local	critical
340053	FreeBSD : OpenSSL -- Multiple vulnerabilities (9008d14d-a0af-11f1-8144-8447094a420f)	Nessus	FreeBSD Local Security Checks	Local	critical
339549	Debian dsa-6465 : libcrypto3-udeb - security update	Nessus	Debian Local Security Checks	Local	critical
339526	Linux Distros Unpatched Vulnerability : CVE-2026-63076	Nessus	Misc.	Local	high
339518	OpenSSL 3.0.0 < 3.0.22 Multiple Vulnerabilities	Nessus	Web Servers	Combined	critical
339490	OpenSSL 3.4.0 < 3.4.7 Multiple Vulnerabilities	Nessus	Web Servers	Combined	critical
335167	OpenSSL 3.5.0 < 3.5.8 Multiple Vulnerabilities	Nessus	Web Servers	Combined	critical
332717	OpenSSL 3.6.0 < 3.6.4 Multiple Vulnerabilities	Nessus	Web Servers	Combined	critical
332232	OpenSSL 4.0.0 < 4.0.2 Multiple Vulnerabilities	Nessus	Web Servers	Combined	critical

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