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CVE-2026-75509 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
GitHub, Inc.
GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-290 Authentication Bypass by Spoofing GitHub, Inc.  
CWE-345 Insufficient Verification of Data Authenticity GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-75509
NVD Published Date:
08/24/2026
NVD Last Modified:
08/24/2026
Source:
GitHub, Inc.