CVE-2026-102274

PyJWT: Malformed RSA JWK aborts parsing of an entire JWK Set

Published Sep 28, 2026 CVSS 3.1 · 5.9 Medium EPSS < 1% KEV · Not listed
Description
PyJWT is a Python implementation of JSON Web Token standards. From 2.9.0 until 2.14.0, PyJWKSet does not catch the plain ValueError raised for malformed RSA JWK components by RSAAlgorithm.from_jwk in jwt/api_jwk.py. This occurs when a JWK Set contains a malformed RSA key alongside otherwise usable keys. As a result, one malformed member aborts construction of the entire PyJWKSet. Consequently, applications can experience authentication failures or request-level denial of service. This issue is fixed in version 2.14.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-w6j9-cwv2-h6wq PyJWT: Malformed RSA JWK aborts parsing of an entire JWK Set
History
Type Values Removed Values Added
First Time appeared Pyjwt Project
Pyjwt Project pyjwt
CPEs cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*
Vendors & Products Pyjwt Project
Pyjwt Project pyjwt
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Jpadilla
Jpadilla pyjwt
Vendors & Products Jpadilla
Jpadilla pyjwt
Type Values Removed Values Added
Description PyJWT is a Python implementation of JSON Web Token standards. From 2.9.0 until 2.14.0, PyJWKSet does not catch the plain ValueError raised for malformed RSA JWK components by RSAAlgorithm.from_jwk in jwt/api_jwk.py. This occurs when a JWK Set contains a malformed RSA key alongside otherwise usable keys. As a result, one malformed member aborts construction of the entire PyJWKSet. Consequently, applications can experience authentication failures or request-level denial of service. This issue is fixed in version 2.14.0.
Title PyJWT: Malformed RSA JWK aborts parsing of an entire JWK Set
Weaknesses CWE-755
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 29, 2026, 7:38 PM
Reserved
Sep 28, 2026, 8:11 PM
Status
Analyzed
Published
Sep 28, 2026, 9:17 PM
Modified
Oct 6, 2026, 6:25 PM
Severity
Moderate
Public date
Sep 28, 2026, 8:42 PM