CVE-2026-102265CWE-674

CVE-2026-102265

Medium · published September 29, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
21.7
In the wild
Unconfirmed
What it is

PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, PyJWS._load in jwt/api_jws.py is affected because parser catches ValueError but not RecursionError. This occurs when a deeply nested token header reaches json.loads. As a result, RecursionError escapes the documented PyJWT error hierarchy. Consequently, an unauthenticated malformed token can cause a request-level failure and HTTP 500. This issue is fixed in version 2.14.0.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00301 · 21.7th percentile
Weakness
CWE-674 · Uncontrolled Recursion
Published
2026-09-29T01:17Z
Affected products (1)
ProductVersionsFixed in
pyjwt_project/pyjwtall versions—
References (4)
https://github.com/jpadilla/pyjwt/commit/06573692ebcdec8831c3927513b3e87c31fbbb62 · [email protected]https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 · [email protected]https://github.com/jpadilla/pyjwt/security/advisories/GHSA-8wjv-2p76-3863 · [email protected]https://github.com/jpadilla/pyjwt/security/advisories/GHSA-8wjv-2p76-3863 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 30 SEP 03:24Z
    EPSS moved — → 0%
    epss
  • 28 SEP 20:48Z
    PyJWT: Uncaught RecursionError in jwt.decode() on deeply nested token header
    cvelistv5