CVE-2026-102946
Deferred
Deferred - Pending Action
Authentication Bypass in joserfc via Empty Signatures Array
Vulnerability report for CVE-2026-102946, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-15
Last updated on: 2026-10-15
Assigner: GitHub, Inc.
Description
Description
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 Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| authlib | joserfc | < 1.7.4 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-345 | The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. |
| CWE-347 | The product does not verify, or incorrectly verifies, the cryptographic signature for data. |
| CWE-290 | This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. |
