{"id":"CVE-2026-101918","title":"PyJWT is a Python implementation of JSON Web Token standards","summary":"PyJWT is a Python implementation of JSON Web Token standards. From 2.0.0a1 until 2.15.0, PyJWT PyJWKClient.get_signing_key_from_jwt is affected because payload parser catches ValueError but not RecursionError. This occurs when an attacke…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","cwe":["CWE-248"],"vendor":"jpadilla","product":"pyjwt","affected":["pyjwt >= 2.0.0a1, < 2.15.0"],"published":"2026-09-28","updated":"2026-09-28","sourceUpdated":"2026-09-28T21:17:13.410","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-101918","references":[{"url":"https://github.com/jpadilla/pyjwt/commit/5fde08a6cf906aa7698de2d6391d88b73006b17b","label":"security-advisories@github.com"},{"url":"https://github.com/jpadilla/pyjwt/releases/tag/2.15.0","label":"security-advisories@github.com"},{"url":"https://github.com/jpadilla/pyjwt/security/advisories/GHSA-42vr-xj54-vc7v","label":"security-advisories@github.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-28T21:20:54.778Z","slug":"CVE-2026-101918","body":"## Overview\n\nPyJWT is a Python implementation of JSON Web Token standards. From 2.0.0a1 until 2.15.0, PyJWT PyJWKClient.get_signing_key_from_jwt is affected because payload parser catches ValueError but not RecursionError. This occurs when an attacker-controlled recursively nested payload reaches json.loads. As a result, documented PyJWT exception handling does not contain the failure. Consequently, an unauthenticated request can raise an exception that may produce an HTTP 500 response. The advisory-defined affected implementation also includes jwt/api_jwt.py, verify_signature=False. This issue is fixed in version 2.15.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}