{"cve":"CVE-2026-101917","nvd":{"published":"2026-09-28T21:17:13.210","modified":"2026-10-07T21:01:01.010","status":"Analyzed","description":"PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT get_signing_key_from_jwt is affected because unknown kid misses force refreshes without a negative cache or minimum refresh interval. This occurs when unauthenticated tokens repeatedly use the same unknown kid or varying kid values absent from the cached JWKS. As a result, each cache miss causes PyJWKClient to refresh the JWKS. Consequently, attacker traffic can amplify outbound requests to the configured JWKS endpoint. This issue is fixed in version 2.14.0.","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-770"],"references":["https://github.com/jpadilla/pyjwt/commit/ba4853a75fb9676362da17f67d0f64bd18afd4e1","https://github.com/jpadilla/pyjwt/releases/tag/2.14.0","https://github.com/jpadilla/pyjwt/security/advisories/GHSA-2gx3-rcp4-g85q","https://github.com/jpadilla/pyjwt/security/advisories/GHSA-2gx3-rcp4-g85q"],"products":["pyjwt_project:pyjwt"],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-101917","score":0.00428,"percentile":0.36732,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-2gx3-rcp4-g85q","url":"https://osv.dev/vulnerability/GHSA-2gx3-rcp4-g85q","summary":"PyJWT: PyJWKClient still amplifies unauthenticated JWKS fetches on unknown kid values (incomplete fix of CVE-2026-48524)","modified":"2026-10-01T17:56:20.150726241Z","packages":[{"ecosystem":"PyPI","name":"pyjwt","purl":"pkg:pypi/pyjwt","ranges":["<2.14.0"],"fixed":["2.14.0"]}]},{"id":"PYSEC-2026-4140","url":"https://osv.dev/vulnerability/PYSEC-2026-4140","summary":"PyJWT: PyJWKClient still amplifies unauthenticated JWKS fetches on unknown kid values (incomplete fix of CVE-2026-48524)","modified":"2026-10-01T17:45:16.627687100Z","packages":[{"ecosystem":"PyPI","name":"pyjwt","purl":"pkg:pypi/pyjwt","ranges":["<2.14.0"],"fixed":["2.14.0"]}]}],"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."]}