Authentication Bypass Affecting joserfc package, versions <1.7.3-1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.09% (1st percentile)

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  • Snyk IDSNYK-DEBIAN14-JOSERFC-19257366
  • published26 Aug 2026
  • disclosed24 Aug 2026

Introduced: 24 Aug 2026

NewCVE-2026-75509  (opens in a new tab)
CWE-290  (opens in a new tab)
CWE-345  (opens in a new tab)

How to fix?

Upgrade Debian:14 joserfc to version 1.7.3-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream joserfc package and not the joserfc package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1