CVE-2026-102265
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.
- CVSS 3.1
- 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 27% of CVEs (scores of 2026-10-25)
- CWE
- CWE-674
- Published
- Modified
- Record from
- the NVD, synced
Affected
- pyjwt_project:pyjwt
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-8wjv-2p76-3863 | PyPI | pyjwt | >=2.13.0 <2.14.0 | 2.14.0 |
| PYSEC-2026-4142 | PyPI | pyjwt | >=2.13.0 <2.14.0 | 2.14.0 |