CVE-2026-102270
mediumPyJWT is a Python implementation of JSON Web Token standards.
Vendor / product: Pyjwt Project — pyjwt
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT is_pem_format is affected because lazy PEM regular expression backtracks extensively. This occurs when a certificate-like input contains repeated BEGIN markers without a matching END marker. As a result, is_pem_format performs unbounded backtracking while searching for a PEM end marker. Consequently, an attacker can cause intensive CPU consumption. This issue is fixed in version 2.14.0.
CVSS
4.9
4.9 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-09-28 21:17
Modified: 2026-10-06 18:46
NVD status: Analyzed
Last synced 3 days ago
Verified against the source API 2026-10-27 06:56 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
pyjwt_project / pyjwt <2.14.0
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Patch / mitigation: https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07
Patch / mitigation: https://github.com/jpadilla/pyjwt/security/advisories/GHSA-jwrc-g2q2-pq5p
Patch / mitigation: https://github.com/jpadilla/pyjwt/security/advisories/GHSA-jwrc-g2q2-pq5p
References
- https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07 security-advisories@github.com
- https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 security-advisories@github.com
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-jwrc-g2q2-pq5p security-advisories@github.com
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-jwrc-g2q2-pq5p 134c704f-9b21-4f2e-91b3-4a467353bcc0
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:56 UTC · record ↗