Incorrect Authorization Affecting authlib package, versions [,1.6.4)
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Start learning- Snyk IDSNYK-PYTHON-AUTHLIB-13003878
- published22 Sept 2025
- disclosed22 Sept 2025
- creditMuhammad Noman Ilyas
Introduced: 22 Sep 2025
NewCVE-2025-59420 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade authlib to version 1.6.4 or higher.
Overview
authlib is a library in building OAuth and OpenID Connect servers.
Affected versions of this package are vulnerable to Incorrect Authorization via the deserialize_compact function. An attacker can bypass intended authorization policies by crafting a signed token with unknown critical header parameters, which are improperly accepted and processed.