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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-49852 Detail

Description

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.6.8, joserfc.jwt.decode accepts attacker-forged HMAC-signed tokens when the caller-supplied verification key is the empty string or None, because HMACAlgorithm.sign and HMACAlgorithm.verify in src/joserfc/_rfc7518/jws_algs.py pass the output of OctKey.get_op_key(...) to hmac.new(...) and OctKey.import_key in src/joserfc/_rfc7518/oct_key.py only emits a SecurityWarning for keys shorter than 14 bytes without rejecting zero-length input. This issue is fixed in version 1.6.8.


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.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 8.7 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/authlib/joserfc/commit/86d00910b2b2d2d07503fee9b572906daefab7f1 GitHub, Inc.
https://github.com/authlib/joserfc/releases/tag/1.6.8 GitHub, Inc.
https://github.com/authlib/joserfc/security/advisories/GHSA-gg9x-qcx2-xmrh GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-287 Improper Authentication GitHub, Inc.  
CWE-326 Inadequate Encryption Strength GitHub, Inc.  
CWE-1391 Use of Weak Credentials GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-49852
NVD Published Date:
07/17/2026
NVD Last Modified:
07/17/2026
Source:
GitHub, Inc.