CVE-2026-102946

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.7.4, joserfc.jws.deserialize_json() accepts a JWS General JSON Serialization with an empty signatures array as authenticated. The verify_general_json() loop performs no iterations for the empty array and returns success because no signature check failed, allowing an attacker without a signing key to supply an arbitrary payload that relying applications may treat as authentic. The issue affects the General JSON Serialization path; compact JWS and JWT decoding, Flattened JSON serialization, and JWE JSON processing do not follow this vulnerable path. This issue is fixed in version 1.7.4.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/authlib/joserfc/commit/f409f8f058225d7686acab6546c94593e4c1bfbe
https://github.com/authlib/joserfc/releases/tag/1.7.4
https://github.com/authlib/joserfc/security/advisories/GHSA-4pp3-559j-c5c2
https://github.com/authlib/joserfc/security/advisories/GHSA-4pp3-559j-c5c2

Configurations

No configuration.

History

15 Oct 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://github.com/authlib/joserfc/security/advisories/GHSA-4pp3-559j-c5c2 -~~	() https://github.com/authlib/joserfc/security/advisories/GHSA-4pp3-559j-c5c2 -

15 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 19:17

Updated : 2026-10-15 20:17

NVD link : CVE-2026-102946

Mitre link : CVE-2026-102946

CVE.ORG link : CVE-2026-102946

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

CWE-345

Insufficient Verification of Data Authenticity

CWE-347

Improper Verification of Cryptographic Signature

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