{"id":"CVE-2026-85394","title":"python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes","summary":"python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pa…","severity":"critical","cvss":9.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-347"],"vendor":"mpdavis","product":"python-jose","affected":["python-jose <= 3.5.0"],"published":"2026-09-03","updated":"2026-09-24","sourceUpdated":"2026-09-24T20:43:32.537","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-85394","references":[{"url":"https://github.com/advisories/GHSA-6c5p-j8vq-pqhj","label":"disclosure@vulncheck.com"},{"url":"https://github.com/mpdavis/python-jose","label":"disclosure@vulncheck.com"},{"url":"https://github.com/mpdavis/python-jose/blob/018b310ddb8b50dcfd09a0c152117835a21dd656/jose/backends/native.py","label":"disclosure@vulncheck.com"},{"url":"https://github.com/mpdavis/python-jose/blob/018b310ddb8b50dcfd09a0c152117835a21dd656/jose/utils.py","label":"disclosure@vulncheck.com"},{"url":"https://github.com/mpdavis/python-jose/issues/414","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/python-jose-through-3.5.0-algorithm-confusion-via-der-encoded-public-key-as-hmac-secret","label":"disclosure@vulncheck.com"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85394"},{"url":"https://github.com/advisories/GHSA-3qf3-8w2g-rqmx"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85394.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-85394"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2528187"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-85394"}],"tags":["nvd","cve.org","ghsa","pip","csaf","vex","red-hat"],"epss":0.00222,"epssPercentile":0.12737,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-14T13:05:35.325975Z"},"ingestedAt":"2026-09-14T15:23:07.411Z","aliases":["GHSA-3qf3-8w2g-rqmx"],"ecosystem":"pip","scores":{"nvd":9.1,"vendor":7.4},"slug":"CVE-2026-85394","body":"## Overview\n\npython-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-85394)\n\nAffected packages:\n\n- `python-jose <= 3.5.0`\n\nSource: https://github.com/advisories/GHSA-3qf3-8w2g-rqmx\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat OpenShift AI (RHOAI) · updated 2026-10-06 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85394.json)","depth":"midnight","depthScore":50,"depthScoreParts":{"impact":50.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}