The Erlang/OTP ssl TLS 1.2 (and earlier) and DTLS client does not verify that the cipher suite selected by the server in ServerHello was among the suites offered by the client in ClientHello. The client-side tls_handshake:hello/5 handler validates the negotiated protocol version and the downgrade sentinel but hands the server-chosen suite directly to ssl_handshake:handle_server_hello_extensions/9, which installs it without a membership check. The TLS 1.3 client path performs this check (per RFC 8446), so it is not affected. An on-path attacker between the client and the intended server can respond with a ServerHello selecting an anonymous key exchange suite such as TLS_DH_anon_* or TLS_ECDH_anon_* that the client never offered. Anonymous suites do not require the server to present a certificate, so the entire verify_peer and cacerts configuration is bypassed: the attacker completes the handshake with its own ephemeral parameters, no certificate is validated, no hostname is checked, and ssl:connect returns {ok, Socket}. All subsequent application traffic is readable and modifiable by the attacker. This issue affects OTP from OTP R13B03 before OTP 27.3.4.15, from OTP 28.0 before OTP 28.5.0.4, and from OTP 29.0 before OTP 29.0.4, corresponding to ssl from 3.10.7 before 11.2.12.11, from 11.3 before 11.6.0.4, and from 11.7 before 11.7.4. Whether OTP before OTP R13B03, corresponding to ssl before 3.10.7, is affected is unknown.

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:3579-1 advisory.

    - CVE-2026-28810: predictable DNS transaction IDs can cause DNS cache poisoning (bsc#1261726).
    - CVE-2026-42789: `public_key` application accepts non-CA certificates as intermediate issuers and this     enables chain       forgery (bsc#1266449).
    - CVE-2026-42790: Name constraints and `Subject CommonName` fallback in TLS hostname verification allows     for certificate       forgery by MITM attacker (bsc#1266466).
    - CVE-2026-42792: permanent `epmd` DoS via connection slot exhaustion due to improper handling of     exceptional       conditions (bsc#1272908).
    - CVE-2026-47078: relative path traversal in `zip:unzip/zip:extract` via `check_dir_level` depth-counter     bypass       (bsc#1272909).
    - CVE-2026-48855: SFTP `READLINK` response leaks absolute backend filesystem path when root is configured     (bsc#1268139).
    - CVE-2026-48856: `httpc` leaks `Authorization` headers to cross-origin redirect targets (bsc#1268141).
    - CVE-2026-48858: server-side request forgery allows FTP bounce attacks and SSRF via an unvalidated `PASV`     response IP       address (bsc#1268142).
    - CVE-2026-48860: `ssl` (`inet_tls_dist` module) allows unauthenticated bypass of the distribution-over-     TLS LAN       allowlist (bsc#1268146).
    - CVE-2026-49759: unbounded stack buffer overflow in SCTP error cause parsing in `inet_drv` (bsc#1268163).
    - CVE-2026-49760: stack buffer overflow in `ei_s_print_term` at very large integer (bsc#1268164).
    - CVE-2026-53422: SFTP `REALPATH` path-existence oracle allows filesystem enumeration outside configured     root       (bsc#1270245).
    - CVE-2026-54886: SSH SFTP server denial of service via extended channel data infinite loop (bsc#1270246).
    - CVE-2026-54887: use of default cryptographic key allows predictable DTLS cookie computation during the     startup window       (bsc#1270247).
    - CVE-2026-54891: plaintext injection towards (D)TLS client during handshake (bsc#1270250).
    - CVE-2026-55737: heap pointer corruption via signed/unsigned mismatch in `LARGE_TUPLE_EXTP` decoding in     `erts`       external term format decoder (bsc#1272910).
    - CVE-2026-55950: time-of-check time-of-use race condition allows an unauthenticated remote attacker to     crash all active       DTLS sessions on a listener (bsc#1270253).
    - CVE-2026-55952: missing validation allows for DoS of the TLS-1.3 server when clients send a malformed     `ClientHello`       with mismatched PSK identity and binder list lengths (bsc#1270258).
    - CVE-2026-55953: TLS 1.2 and DTLS clients accept unoffered anonymous cipher suites and allow for server     authentication       bypass (bsc#1272911).
    - CVE-2026-58227: TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate     chain       (bsc#1272913).
    - CVE-2026-59250: `megaco` flex scanner buffer overflow via oversized property parm name (bsc#1272914).
    - CVE-2026-59251: denial of service via exponential certificate policy tree growth in path validation     (bsc#1272915).

Tenable has extracted the preceding description block directly from the SUSE 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 Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-4220305a93 advisory.

    CVE-2026-55953

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

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

The remote Fedora 44 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-7a3db128e8 advisory.

    CVE-2026-55953

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

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

The version of Erlang/OTP installed on the remote host is 17.0 prior to 27.3.4.15, 28.0 prior to 28.5.0.4, or 29.0 prior to 29.0.4. It is, therefore, affected by multiple vulnerabilities:

  - The Erlang/OTP ssl TLS 1.2 (and earlier) and DTLS client does not verify that the cipher suite     selected by the server in ServerHello was among the suites offered by the client in ClientHello.
    An on-path attacker can respond with a ServerHello selecting an anonymous key exchange suite,     bypassing certificate validation and allowing interception of traffic. (CVE-2026-55953)

  - Classic buffer overflow in the Erlang/OTP megaco flex scanner C driver allows a remote     unauthenticated attacker to corrupt the driver's memory by sending a single text-encoded     H.248/Megaco message containing an oversized property parm name. (CVE-2026-59250)

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.

  - The Erlang/OTP ssl TLS 1.2 (and earlier) and DTLS client does not verify that the cipher suite selected by     the server in ServerHello was among the suites offered by the client in ClientHello. The client-side     tls_handshake:hello/5 handler validates the negotiated protocol version and the downgrade sentinel but     hands the server-chosen suite directly to ssl_handshake:handle_server_hello_extensions/9, which installs     it without a membership check. The TLS 1.3 client path performs this check (per RFC 8446), so it is not     affected. An on-path attacker between the client and the intended server can respond with a ServerHello     selecting an anonymous key exchange suite such as TLS_DH_anon_* or TLS_ECDH_anon_* that the client never     offered. Anonymous suites do not require the server to present a certificate, so the entire verify_peer     and cacerts configuration is bypassed: the attacker completes the handshake with its own ephemeral     parameters, no certificate is validated, no hostname is checked, and ssl:connect returns {ok, Socket}. All     subsequent application traffic is readable and modifiable by the attacker. This issue affects OTP from OTP     R13B03 before OTP 27.3.4.15, from OTP 28.0 before OTP 28.5.0.4, and from OTP 29.0 before OTP 29.0.4,     corresponding to ssl from 3.10.7 before 11.2.12.11, from 11.3 before 11.6.0.4, and from 11.7 before     11.7.4. Whether OTP before OTP R13B03, corresponding to ssl before 3.10.7, is affected is unknown.
    (CVE-2026-55953)

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

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the 445c61c0-89e1-11f1-b35c-4c526214c986 advisory.

    https://github.com/erlang/otp/security/advisories/GHSA-c6cw-pr89-w882 reports:
    The OTP TLS/DTLS client (pre TLS-1.3) does not verify that               the cipher suite selected by the server in ServerHello is one               of those offered in ClientHello. A man-in-the-middle attacker               can select an anonymous cipher suite such as ECDH_anon that               was never offered by the client. Since anonymous suites do not               require a server certificate, this completely bypasses the               client's verify_peer setting, giving the attacker a fully               established connection without possessing any trusted               certificate, and thus complete read and modify access to the               transmitted data. TLS-1.3 is not affected.

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

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

ID	Name	Product	Family	Type	Severity
335097	SUSE SLES15 Security Update : erlang26 (SUSE-SU-2026:3579-1)	Nessus	SuSE Local Security Checks	Local	critical
333508	Fedora 43 : erlang (2026-4220305a93)	Nessus	Fedora Local Security Checks	Local	critical
333501	Fedora 44 : erlang (2026-7a3db128e8)	Nessus	Fedora Local Security Checks	Local	critical
331349	Erlang/OTP 17.0 < 27.3.4.15 / 28.0 < 28.5.0.4 / 29.0 < 29.0.4 Multiple Vulnerabilities	Nessus	Misc.	Local	critical
330402	Linux Distros Unpatched Vulnerability : CVE-2026-55953	Nessus	Misc.	Local	critical
330268	FreeBSD : Erlang/OTP -- (D)TLS-1.2 server certificate verification bypass (445c61c0-89e1-11f1-b35c-4c526214c986)	Nessus	FreeBSD Local Security Checks	Local	critical

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