Open redirect in authlib - CVE-2026-41479
Published: June 8, 2026
Vulnerability identifier: #VU133912
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-41479
CWE-ID: CWE-601
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Authlib
Affected software:
authlib
authlib
Detailed vulnerability description
The vulnerability allows a remote attacker to redirect users to an attacker-controlled URL.
The vulnerability exists due to url redirection to untrusted site in the OAuth 2.0 authorization endpoint when handling an authorization request with an unsupported response_type and a supplied redirect_uri. A remote attacker can send a specially crafted authorization request to redirect users to an attacker-controlled URL.
The redirect occurs before client lookup and before any redirect URI validation, and no valid client registration or authenticated user is required.
How to mitigate CVE-2026-41479
Install security update from vendor's website.