{"cve":"CVE-2026-101918","nvd":{"published":"2026-09-28T21:17:13.410","modified":"2026-10-07T20:59:17.860","status":"Analyzed","description":"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 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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-248"],"references":["https://github.com/jpadilla/pyjwt/commit/5fde08a6cf906aa7698de2d6391d88b73006b17b","https://github.com/jpadilla/pyjwt/releases/tag/2.15.0","https://github.com/jpadilla/pyjwt/security/advisories/GHSA-42vr-xj54-vc7v"],"products":["pyjwt_project:pyjwt"],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-101918","score":0.00413,"percentile":0.3529,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-42vr-xj54-vc7v","url":"https://osv.dev/vulnerability/GHSA-42vr-xj54-vc7v","summary":"PyJWT: Unauthenticated RecursionError DoS in pre-verification payload parse (PyJWKClient.get_signing_key_from_jwt / verify_signature=False)","modified":"2026-10-01T17:56:09.538835697Z","packages":[{"ecosystem":"PyPI","name":"pyjwt","purl":"pkg:pypi/pyjwt","ranges":[">=2.0.0a1 <2.15.0"],"fixed":["2.15.0"]}]},{"id":"PYSEC-2026-4141","url":"https://osv.dev/vulnerability/PYSEC-2026-4141","summary":"PyJWT: Unauthenticated RecursionError DoS in pre-verification payload parse (PyJWKClient.get_signing_key_from_jwt / verify_signature=False)","modified":"2026-10-01T17:45:16.836914789Z","packages":[{"ecosystem":"PyPI","name":"pyjwt","purl":"pkg:pypi/pyjwt","ranges":[">=2.0.0a1 <2.15.0"],"fixed":["2.15.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}