PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, HMACAlgorithm.from_jwk is affected because PyJWK verification path used the decoded key without applying prepare_key validation. This occurs when a trusted JWK Set contains an oct entry with an empty k value. As a result, an attacker signs an HMAC token with the same zero-length key accepted by PyJWT. Consequently, forged token can carry arbitrary authenticated claims. This issue is fixed in version 2.14.0.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:87004 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-gateway: authorization bypass via workload identity token forgery (CVE-2026-94416)
    * automation-platform-ui: proxy-addr vulnerable to IP spoofing via IPv4-mapped IPv6 trust subnet     (CVE-2026-90711)
    * automation-platform-ui: compression: Denial of Service via memory leak on premature response close     (CVE-2026-87776)
    * automation-platform-ui: fflate: Denial of Service via crafted ZIP archives (CVE-2026-45820)
    * python3.12-pulpcore: file:// scheme allowlist bypass in content upload file_url field enables arbitrary     file read and Pulp Container registry signing key theft (CVE-2026-90959)
    * python3.12-pyjwt: Verification key substitution via unvalidated JWKS redirects (CVE-2026-102267)
    * python3.12-pyjwt: Token forgery via improper Unicode byte-order mark handling (CVE-2026-102272)
    * python3.12-pyjwt: Authentication bypass via empty HMAC key acceptance (CVE-2026-102266)
    * python3.12-pyjwt: Authentication bypass via acceptance of DER public keys as HMAC secrets     (CVE-2026-102271)
    * python3.12-pyjwt: Token forgery via acceptance of public JWK containers as HMAC secrets     (CVE-2026-102273)

    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 version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:1087 advisory.

    Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

    CVE-2026-102272:
    PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0,     HMACAlgorithm.prepare_key in jwt/algorithms.py is affected because raw-JWK detector does not normalize     accepted Unicode byte-order marks before checking for JSON. This occurs when a public JWK is prefixed with     a UTF-8 BOM and used in a mixed-algorithm verification path. As a result, public JWK bypasses asymmetric-     key detection and becomes the HMAC secret. Consequently, an attacker who knows the public key can forge     authenticated tokens. This issue is fixed in version 2.14.0.

    CVE-2026-102268:
    PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in     jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the     cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a     mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized     asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge     authenticated HMAC tokens. This issue is fixed in version 2.14.0.

    CVE-2026-102266:
    PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0,     HMACAlgorithm.from_jwk is affected because PyJWK verification path used the decoded key without applying     prepare_key validation. This occurs when a trusted JWK Set contains an oct entry with an empty k value. As     a result, an attacker signs an HMAC token with the same zero-length key accepted by PyJWT. Consequently,     forged token can carry arbitrary authenticated claims. This issue is fixed in version 2.14.0.

Tenable has extracted the preceding description block directly from the Tencent 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 a vulnerability referenced in the following CVE:

  - PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0,
    HMACAlgorithm.from_jwk is affected because PyJWK verification path used the decoded key without applying
    prepare_key validation. This occurs when a trusted JWK Set contains an oct entry with an empty k value. As
    a result, an attacker signs an HMAC token with the same zero-length key accepted by PyJWT. Consequently,
    forged token can carry arbitrary authenticated claims. This issue is fixed in version 2.14.0.
    (CVE-2026-102266)

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

  - PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0,     HMACAlgorithm.from_jwk is affected because PyJWK verification path used the decoded key without applying     prepare_key validation. This occurs when a trusted JWK Set contains an oct entry with an empty k value. As     a result, an attacker signs an HMAC token with the same zero-length key accepted by PyJWT. Consequently,     forged token can carry arbitrary authenticated claims. This issue is fixed in version 2.14.0.
    (CVE-2026-102266)

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

ID	Name	Product	Family	Type	Severity
370142	RHEL 9 : Red Hat Ansible Automation Platform 2.6 Product Security and Bug Fix Update (Important) (RHSA-2026:87004)	Nessus	Red Hat Local Security Checks	Local	high
365155	TencentOS Server 4: python-jwt (TSSA-2026:1087)	Nessus	Tencent Local Security Checks	Local	critical
465715	Echo: pyjwt: security update to 2.14.0	Tenable Cloud Security	Echo Local Security Checks	Local	critical
465715	Echo: pyjwt: security update to 2.14.0	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	critical
351337	Linux Distros Unpatched Vulnerability : CVE-2026-102266	Nessus	Misc.	Local	critical

Detections

Analytics

CVE-2026-102266

critical

Tenable Plugins

high

critical

critical

critical

critical