CVE-2026-102265PyJWT: Uncaught RecursionError in jwt.decode() on deeply nested token header
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
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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
- 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Weakness (CWE)
- CWE-674
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Analyzed
- Record last updated
- Oct 1, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
jpadilla pyjwt jpadilla:pyjwt (from the name) | from 2.13.0, < 2.14.0 | CNA record |
pyjwt_project pyjwt pyjwt_project:pyjwt | 2.13.0 | NVD |
References
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-8wjv-2p76-3863x-refsource-confirm, exploit, mitigation, vendor-advisory
- https://github.com/jpadilla/pyjwt/commit/06573692ebcdec8831c3927513b3e87c31fbbb62x-refsource-misc, patch
- https://github.com/jpadilla/pyjwt/releases/tag/2.14.0x-refsource-misc, product, release-notes
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.