{"id":"CVE-2026-102271","title":"PyJWT is a Python implementation of JSON Web Token standards","summary":"PyJWT is a Python implementation of JSON Web Token standards. From 2.4.0 until 2.14.0, PyJWT HMACAlgorithm.prepare_key is affected because asymmetric-key guard relies on textual markers that are absent from DER encoding. This occurs when…","severity":"high","cvss":7.4,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-347"],"vendor":"pyjwt_project","product":"pyjwt","affected":["pyjwt >= 2.4.0, < 2.14.0"],"patched":["pyjwt 2.14.0"],"published":"2026-09-28","updated":"2026-10-06","sourceUpdated":"2026-10-06T18:36:16.047","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-102271","references":[{"url":"https://github.com/jpadilla/pyjwt/commit/2798504fa2663364573cf2d1043d8d7fef389499","label":"security-advisories@github.com"},{"url":"https://github.com/jpadilla/pyjwt/releases/tag/2.14.0","label":"security-advisories@github.com"},{"url":"https://github.com/jpadilla/pyjwt/security/advisories/GHSA-p4g4-x82p-q773","label":"security-advisories@github.com"},{"url":"https://github.com/jpadilla/pyjwt/security/advisories/GHSA-p4g4-x82p-q773","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102271.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-102271"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2542687"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-102271"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102271"},{"url":"https://github.com/advisories/GHSA-p4g4-x82p-q773"},{"url":"https://github.com/jpadilla/pyjwt"},{"url":"https://pypi.org/project/pyjwt"},{"url":"https://access.redhat.com/errata/RHSA-2026:82415"},{"url":"https://access.redhat.com/errata/RHSA-2026:82368"},{"url":"https://access.redhat.com/errata/RHSA-2026:82061"},{"url":"https://access.redhat.com/errata/RHSA-2026:82059"},{"url":"https://access.redhat.com/errata/RHSA-2026:82371"},{"url":"https://access.redhat.com/errata/RHSA-2026:87004"},{"url":"https://access.redhat.com/errata/RHSA-2026:87120"},{"url":"https://access.redhat.com/errata/RHSA-2026:87124"}],"tags":["nvd","cve.org","exploit-available","csaf","vex","red-hat","ghsa","pip","osv"],"epss":0.00215,"epssPercentile":0.11783,"aliases":["GHSA-p4g4-x82p-q773","PYSEC-2026-4149"],"ecosystem":"pip","exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"total","timestamp":"2026-10-01T14:57:03.181101Z"},"ingestedAt":"2026-09-28T21:20:54.781Z","slug":"CVE-2026-102271","body":"## Overview\n\nPyJWT is a Python implementation of JSON Web Token standards. From 2.4.0 until 2.14.0, PyJWT HMACAlgorithm.prepare_key is affected because asymmetric-key guard relies on textual markers that are absent from DER encoding. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a DER public key as the shared verification key. As a result, PyJWT uses public DER bytes 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.\n\n## Affected\n\n- `pyjwt >= 2.4.0, < 2.14.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `pyjwt 2.14.0`\n\n## Package advisory (CVE-2026-102271)\n\nAffected packages:\n\n- `pyjwt >= 2.4.0, < 2.14.0`\n\nPatched in:\n\n- `pyjwt 2.14.0`\n\nSource: https://github.com/advisories/GHSA-p4g4-x82p-q773\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Ansible Automation Orchestrator 2026, Lightspeed Core, Red Hat AI Inference Server, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, … · no fix planned: Ansible Automation Orchestrator 2026, Lightspeed Core, Red Hat AI Inference Server, Red Hat Ansible Automation Platform 2, … · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102271.json)\n- **RHSA-2026:82415** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82415)\n- **RHSA-2026:82368** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82368)\n- **RHSA-2026:82061** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82061)\n- **RHSA-2026:82059** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82059)\n- **RHSA-2026:82371** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82371)\n- **RHSA-2026:87004** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.6 for RHEL 9 · released 2026-10-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:87004)\n- **RHSA-2026:87120** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.6 · released 2026-10-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:87120)\n- **RHSA-2026:87124** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.7 · released 2026-10-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:87124)","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":40.7,"likelihood":0,"exploitation":12,"ransomware":0},"changes":[{"seq":214343,"id":"CVE-2026-102271","ts":1790869743007,"field":"exploit_available","old":"false","new":"true"}]}