VULNERABILITY INTELLIGENCE
CVE-2026-75509
CVSS score6.5 MEDIUM
EPSS probability0.12%
CISA KEVNot currently listed
Published2026-08-24
Last modified2026-10-12
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N
Description
joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to version 1.7.3, JWTClaimsRegistry applies membership matching to list-valued iss and sub claims, allowing an array-valued iss that contains the expected issuer to pass an intended equality check and enabling issuer-validation bypass. This issue is fixed in version 1.7.3.
Weakness classification
- security-advisories@github.com: CWE-290