Description
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT signature segment is affected because signature segment decoding accepts characters outside the canonical Base64URL representation. This occurs when non-Base64URL characters are appended to a valid compact JWS signature segment. As a result, base64url_decode produces the same signature bytes for different serialized segments. Consequently, raw-token revocation checks can fail to recognize an equivalent modified token. This issue is fixed in version 2.14.0.
Affected products
pyjwt_project: pyjwt
References3
- github.com/jpadilla/pyjwt/security/advisories/GHSA-hxm8-2xgr-2p… ExploitMitigationVendor Advisory
- github.com/jpadilla/pyjwt/commit/e6f48401001609a8f99e71fcaf355f… Patch
- github.com/jpadilla/pyjwt/releases/tag/2.14.0 ProductRelease Notes
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 13 · as of 9 November 2026
- CWE
- CWE-180
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