CVE-2026-102270
PyJWT: ReDoS vulnerability when calling the `is_pem_format` function.
- State
- Published
- Severity
- 4.4 Medium
- Published
- Sep 28, 2026
- Updated
- Sep 29, 2026
- Reserved
- Sep 28, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.4 Medium | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-1333 Inefficient Regular Expression Complexity
Affected Products
| Product | Versions |
|---|---|
pyjwtjpadilla |
|
References
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