CVE-2026-102269

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.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/jpadilla/pyjwt/commit/e6f48401001609a8f99e71fcaf355fb895d508a8	Patch
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0	Product Release Notes
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-hxm8-2xgr-2p9m	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*

History

06 Oct 2026, 18:54

Type	Values Removed	Values Added
References	~~() https://github.com/jpadilla/pyjwt/commit/e6f48401001609a8f99e71fcaf355fb895d508a8 -~~	() https://github.com/jpadilla/pyjwt/commit/e6f48401001609a8f99e71fcaf355fb895d508a8 - Patch
References	~~() https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 -~~	() https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 - Product, Release Notes
References	~~() https://github.com/jpadilla/pyjwt/security/advisories/GHSA-hxm8-2xgr-2p9m -~~	() https://github.com/jpadilla/pyjwt/security/advisories/GHSA-hxm8-2xgr-2p9m - Exploit, Mitigation, Vendor Advisory
First Time		Pyjwt Project pyjwt Pyjwt Project
CPE		cpe:2.3:a:pyjwt_project:pyjwt::::::::

28 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-28 21:17

Updated : 2026-10-06 18:54

NVD link : CVE-2026-102269

Mitre link : CVE-2026-102269

CVE.ORG link : CVE-2026-102269

JSON object : View

Products Affected

pyjwt_project

pyjwt

CWE

CWE-180

Incorrect Behavior Order: Validate Before Canonicalize

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