Bug 2542686 (CVE-2026-102270) - CVE-2026-102270 pyjwt: pyjwt: Denial of Service via regular expression backtracking in is_pem_format
Summary: CVE-2026-102270 pyjwt: pyjwt: Denial of Service via regular expression backtr...
Keywords:
Status: NEW
Alias: CVE-2026-102270
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security
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Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-28 20:46 UTC by OSIDB Bzimport
Modified: 2026-09-28 20:52 UTC (History)
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Description OSIDB Bzimport 2026-09-28 20:46:09 UTC 
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.
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