CVE-2026-102270PyJWT: ReDoS vulnerability when calling the `is_pem_format` function.

Descripción

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.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/jpadilla/pyjwt/security/advisories/GHSA-jwrc-g2q2-pq5p ExploitPatchVendor Advisory
• https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07 Patch
• https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 ProductRelease Notes