pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long are now rejected.

According to the versions of the pyOpenSSL packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

    pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version     26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than     256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values     that are too long are now rejected.(CVE-2026-27459)

    pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version     26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception,     this would result in a connection being accepted. If a user was relying on this callback for any security-     sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now     result in rejecting the connection.(CVE-2026-27448)

Tenable has extracted the preceding description block directly from the EulerOS pyOpenSSL 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 pyOpenSSL installed on the remote host is prior to 26.0.0. It is, therefore, affected by a buffer overflow vulnerability:

  - pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0,     if a user provided callback to set_cookie_generate_callback returned a cookie value greater than 256 bytes,     pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long     are now rejected. (CVE-2026-27459)

Note that Nessus has not tested for this issue 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-2026:14873 advisory.

    Red Hat Satellite is a system management solution that allows organizations     to configure and maintain their systems without the necessity to provide     public Internet access to their servers or other client systems. It     performs provisioning and configuration management of predefined standard     operating environments.

    Security Fix(es):

    * python-pillow: Pillow: Out-of-bounds Write via Specially Crafted PSD Image (CVE-2026-25990)

    * candlepin: mchange-commons-java: Arbitrary code execution via JNDI dereferencing of crafted objects     (CVE-2026-27727)

    * python-markdown: denial of service via malformed HTML-like sequences (CVE-2025-69534)

    * python-pyOpenSSL: DTLS cookie callback buffer overflow (CVE-2026-27459)

    * rubygem-activesupport: Active Support: Denial of Service via large scientific notation strings     (CVE-2026-33176)

    Bug Fix(es):

    * Satellite manifest consumer profile cert and key found in satellite client rhsm cache (SAT-43920)

    * All communication should happen only over https during global registration execution (SAT-43921)

    * Impossible to generate registration command via REST API in isolated networks managed by external     capsules (SAT-43922)

    * Errata applicability and Refresh applicability tasks for RHEL 7 hosts runs dnf command. (SAT-43923)

    * BIOS info is not populated in All hosts page and in Host Details tab (SAT-43925)

    * Executing the 'katello::clean_backend_objects' rake task takes a long time to complete (SAT-43926)

    * Puppet fact parser can't create OS entry blocking Satellite leapp upgrades (SAT-43928)

    * No repositories available through subscriptions on a cloud-instance host after registering it to Red Hat     Satellite using global registration method (SAT-43929)

    * Proxy password shown in clear text in the Overview page of Virt-who Configuration (SAT-43931)

    * Non-admin users on Satellite with viewer role, unable to see the hostgroup. (SAT-44039)

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 8 / 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:14874 advisory.

    Red Hat Satellite is a system management solution that allows organizations     to configure and maintain their systems without the necessity to provide     public Internet access to their servers or other client systems. It     performs provisioning and configuration management of predefined standard     operating environments.

    Security Fix(es):

    * python-pillow: Pillow: Out-of-bounds Write via Specially Crafted PSD Image (CVE-2026-25990)

    * candlepin: mchange-commons-java: Arbitrary code execution via JNDI dereferencing of crafted objects     (CVE-2026-27727)

    * python-markdown: denial of service via malformed HTML-like sequences (CVE-2025-69534)

    * python-pyOpenSSL: DTLS cookie callback buffer overflow (CVE-2026-27459)

    * rubygem-activesupport: Active Support: Denial of Service via large scientific notation strings     (CVE-2026-33176)

    Bug Fix(es):

    * Satellite manifest consumer profile cert and key found in satellite client rhsm cache (SAT-43030)

    * All communication should happen only over https during global registration execution (SAT-44031)

    * Impossible to generate registration command via REST API in isolated networks managed by external     capsules (SAT-44032)

    * Executing the 'katello::clean_backend_objects' rake task takes a long time to complete (SAT-44033)

    * Puppet fact parser can't create OS entry blocking Satellite leapp upgrades (SAT-44035)

    * No repositories available through subscriptions on a cloud-instance host after registering it to Red Hat     Satellite using global registration method (SAT-44036)

    * Proxy password shown in clear text in the Overview page of Virt-who Configuration (SAT-43834)

    * Non-admin users on Satellite with viewer role, unable to see the hostgroup. (SAT-44034)

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 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:14835 advisory.

    Red Hat Satellite is a system management solution that allows organizations     to configure and maintain their systems without the necessity to provide     public Internet access to their servers or other client systems. It     performs provisioning and configuration management of predefined standard     operating environments.

    Security Fix(es):

    * python3.12-django: Django: SQL Injection via crafted column aliases     (CVE-2026-1287)
    * python3.12-django: Django: SQL Injection via RasterField band index     parameter (CVE-2026-1207)
    * python3.12-django: Django: SQL injection via crafted column aliases in     QuerySet.order_by() (CVE-2026-1312)
    * python3.12-django: Django: Denial of Service via crafted HTML inputs     (CVE-2026-1285)
    * python3.12-django: Django: Denial of Service via crafted request with     duplicate headers (CVE-2025-14550)
    * python3.12-markdown: markdown: Denial of Service via malformed     HTML-like sequences (CVE-2025-69534)
    * python3.12-pyOpenSSL: pyOpenSSL: DTLS cookie callback buffer overflow     (CVE-2026-27459)
    * rubygem-activesupport: Active Support: Denial of Service via large     scientific notation strings (CVE-2026-33176)

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 8 / 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:13512 advisory.

    Red Hat Ansible Automation Platform provides an enterprise framework for building, deploying and managing     IT automation at scale. IT Managers can provide top-down guidelines on how automation is applied to     individual teams, while automation developers retain the freedom to write tasks that leverage existing     knowledge without the overhead. Ansible Automation Platform makes it possible for users across an     organization to share, vet, and manage automation content by means of a simple, powerful, and agentless     language.

    Security Fix(es):
    * automation-controller: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * automation-controller: PyJWT accepts unknown `crit` header extensions (RFC 7515 4.1.11 MUST violation)     (CVE-2026-32597)
    * automation-controller: denial of service via malformed HTML-like sequences (CVE-2025-69534)
    * automation-controller: cryptography Subgroup Attack Due to Missing Subgroup Validation for SECT Curves     (CVE-2026-26007)
    * automation-gateway: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * automation-gateway: Rollup: Remote Code Execution via Path Traversal Vulnerability (CVE-2026-27606)
    * automation-gateway: SVGO: Denial of Service via XML entity expansion (CVE-2026-29074)
    * automation-gateway: ReDoS via $data reference (CVE-2025-69873)
    * automation-gateway-proxy: Incorrect parsing of IPv6 host literals in net/url (CVE-2026-25679)
    * python3.12-django-ansible-base: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * python3.12-markdown: denial of service via malformed HTML-like sequences (CVE-2025-69534)
    * python3.12-jwcrypto: JWCrypto: Memory exhaustion via crafted compressed JWE tokens (CVE-2026-39373)
    * python3.12-pyasn1: pyasn1 Vulnerable to Denial of Service via Unbounded Recursion (CVE-2026-30922)
    * python3.12-pyasn1: pyasn1: Denial of Service due to memory exhaustion from malformed RELATIVE-OID     (CVE-2026-23490)
    * python3.12-pyOpenSSL: DTLS cookie callback buffer overflow (CVE-2026-27459)
    * receptor: Incorrect parsing of IPv6 host literals in net/url (CVE-2026-25679)

    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.

    For details about this release, refer to the release notes 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 / 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:13508 advisory.

    Red Hat Ansible Automation Platform provides an enterprise framework for building, deploying and managing     IT automation at scale. IT Managers can provide top-down guidelines on how automation is applied to     individual teams, while automation developers retain the freedom to write tasks that leverage existing     knowledge without the overhead. Ansible Automation Platform makes it possible for users across an     organization to share, vet, and manage automation content by means of a simple, powerful, and agentless     language.

    Security Fix(es):
    * automation-controller: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * automation-controller: DTLS cookie callback buffer overflow (CVE-2026-27459)
    * automation-controller: PyJWT accepts unknown `crit` header extensions (RFC 7515 4.1.11 MUST violation)     (CVE-2026-32597)
    * automation-controller: denial of service via malformed HTML-like sequences (CVE-2025-69534)
    * automation-gateway: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * automation-gateway-proxy: Incorrect parsing of IPv6 host literals in net/url (CVE-2026-25679)
    * automation-platform-ui: Rollup: Remote Code Execution via Path Traversal Vulnerability (CVE-2026-27606)
    * automation-platform-ui: minimatch: Denial of Service via specially crafted glob patterns     (CVE-2026-26996)
    * python3.12-django-ansible-base: Account hijacking and unauthorized access via unverified email linking     (CVE-2026-6266)
    * python3.12-markdown: denial of service via malformed HTML-like sequences (CVE-2025-69534)
    * python3.12-jwcrypto: JWCrypto: Memory exhaustion via crafted compressed JWE tokens (CVE-2026-39373)
    * python3.12-pyasn1: pyasn1 Vulnerable to Denial of Service via Unbounded Recursion (CVE-2026-30922)
    * python3.12-pyasn1: pyasn1: Denial of Service due to memory exhaustion from malformed RELATIVE-OID     (CVE-2026-23490)
    * python3.12-pyOpenSSL: DTLS cookie callback buffer overflow (CVE-2026-27459)
    * receptor: Incorrect parsing of IPv6 host literals in net/url (CVE-2026-25679)

    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.

    For details about this release, refer to the release notes 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.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 0.14.0 and prior to version
    26.0.0, if a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception,
    this would result in a connection being accepted. If a user was relying on this callback for any security-
    sensitive behavior, this could allow bypassing it. Starting in version 26.0.0, unhandled exceptions now
    result in rejecting the connection. (CVE-2026-27448)

  - pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version
    26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than
    256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values
    that are too long are now rejected. (CVE-2026-27459)

The remote Redhat Enterprise Linux 8 host has a package installed that is affected by a vulnerability as referenced in the RHSA-2026:10754 advisory.

    Red Hat Update Infrastructure (RHUI) provides a highly scalable and redundant framework for managing     repositories and content. It also allows cloud providers to deliver content and updates to Red Hat     Enterprise Linux (RHEL) instances.

    Security Fixes:
    * pyOpenSSL: DTLS cookie callback buffer overflow (CVE-2026-27459)

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

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

An update of the python3 package has been released.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has a package installed that is affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:1192-1 advisory.

    - CVE-2026-27448: unhandled exception can result in connection not being cancelled (bsc#1259804).
    - CVE-2026-27459: large cookie value can lead to a buffer overflow (bsc#1259808).

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 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-5697f4e025 advisory.

    Update to version 26.0.0

    - Added support for using aws-lc instead of OpenSSL.
    - Properly raise an error if a DTLS cookie callback returned a cookie       longer than DTLS1_COOKIE_LENGTH bytes. Previously this would result in       a buffer-overflow. Credit to dark_haxor for reporting the issue.
      CVE-2026-27459
    - Added OpenSSL.SSL.Connection.get_group_name to determine which group       name was negotiated.
    - Context.set_tlsext_servername_callback now handles exceptions raised       in the callback by calling sys.excepthook and returning a fatal TLS       alert. Previously, exceptions were silently swallowed and the       handshake would proceed as if the callback had succeeded. Credit to       Leury Castillo for reporting this issue. CVE-2026-27448


Tenable has extracted the preceding description block directly from the Fedora 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 openSUSE 16 host has a package installed that is affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:20419-1 advisory.

    - CVE-2026-27448: unhandled exception can result in connection not being cancelled (bsc#1259804).
    - CVE-2026-27459: large cookie value can lead to a buffer overflow (bsc#1259808).

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 packages installed that are affected by a vulnerability as referenced in the FEDORA-2026-9d5b9f45ec advisory.

    - Update pyOpenSSL to v26.0.0 (security update)
    - Update python-cryptography to v46.0.5 (dependency of pyOpenSSL 26)
    - Update rust-asn1 to 0.22 (dependency of python-cryptography)
    - Update kryoptic to v1.5 (required for rust-asn1 bump to 0.22)

    The security status of this update is _only_ for pyOpenSSL.

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 Ubuntu 22.04 LTS / 24.04 LTS / 25.10 host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-8115-1 advisory.

    It was discovered that pyOpenSSL incorrectly handled exceptions in the tlsext_servername callback. This     could result in connections being accepted after an exception, contrary to expectations. (CVE-2026-27448)

    It was discovered that pyOpenSSL incorrectly handled the DTLS cookie generation callback. If a callback     provided cookie values greater than 256 bytes, an attacker could use this issue to cause pyOpenSSL to     crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected     Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-27459)

Tenable has extracted the preceding description block directly from the Ubuntu 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.

  - pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version     26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than     256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values     that are too long are now rejected. (CVE-2026-27459)

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

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version
    26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than
    256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values
    that are too long are now rejected. (CVE-2026-27459)

ID	Name	Product	Family	Severity
323198	EulerOS 2.0 SP15 : pyOpenSSL (EulerOS-SA-2026-2458)	Nessus	Huawei Local Security Checks	critical
323159	EulerOS 2.0 SP15 : pyOpenSSL (EulerOS-SA-2026-2499)	Nessus	Huawei Local Security Checks	critical
318387	pyOpenSSL 22.0.x < 26.0.0 Buffer Overflow	Nessus	Misc.	critical
313174	RHEL 9 : Satellite 6.17.8 Async Update (Important) (RHSA-2026:14873)	Nessus	Red Hat Local Security Checks	critical
313105	RHEL 8 / 9 : Satellite 6.16.8 Async Update (Important) (RHSA-2026:14874)	Nessus	Red Hat Local Security Checks	critical
313104	RHEL 9 : Satellite 6.18.5 Async Update (Important) (RHSA-2026:14835)	Nessus	Red Hat Local Security Checks	critical
312098	RHEL 8 / 9 : Red Hat Ansible Automation Platform 2.5 Product Security and Bug Fix Update (Important) (RHSA-2026:13512)	Nessus	Red Hat Local Security Checks	critical
312090	RHEL 10 / 9 : Red Hat Ansible Automation Platform 2.6 Product Security and Bug Fix Update (Important) (RHSA-2026:13508)	Nessus	Red Hat Local Security Checks	critical
440908	Alpine: multiple py3-openssl packages: security update to 26.1.0-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	critical
440908	Alpine: multiple py3-openssl packages: security update to 26.1.0-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	critical
310412	RHEL 8 : RHUI 4.11.4 security update - python-pyOpenSSL (Important) (RHSA-2026:10754)	Nessus	Red Hat Local Security Checks	critical
307419	Photon OS 4.0: Python3 PHSA-2026-4.0-1000	Nessus	PhotonOS Local Security Checks	critical
305283	SUSE SLED15 / SLES15 / openSUSE 15 Security Update : python-pyOpenSSL (SUSE-SU-2026:1192-1)	Nessus	SuSE Local Security Checks	critical
305118	Photon OS 5.0: Python3 PHSA-2026-5.0-0802	Nessus	PhotonOS Local Security Checks	critical
304349	Fedora 44 : pyOpenSSL (2026-5697f4e025)	Nessus	Fedora Local Security Checks	critical
304227	openSUSE 16 Security Update : python-pyOpenSSL (openSUSE-SU-2026:20419-1)	Nessus	SuSE Local Security Checks	critical
303921	Fedora 43 : kryoptic / pyOpenSSL / python-cryptography / rust-asn1 / etc (2026-9d5b9f45ec)	Nessus	Fedora Local Security Checks	critical
303750	Ubuntu 22.04 LTS / 24.04 LTS / 25.10 : pyOpenSSL vulnerabilities (USN-8115-1)	Nessus	Ubuntu Local Security Checks	critical
302890	Linux Distros Unpatched Vulnerability : CVE-2026-27459	Nessus	Misc.	critical
438840	SCA: security update for pyopenssl (GHSA-5pwr-322w-8jr4)	Tenable Cloud Security	SCA Checks	critical
438840	SCA: security update for pyopenssl (GHSA-5pwr-322w-8jr4)	Tenable Self-Hosted Container Security	SCA Checks	critical

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