Open redirect in authlib - CVE-2026-44681
Published: May 11, 2026
Vulnerability identifier: #VU130999
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:U/U:Green
CVE-ID: CVE-2026-44681
CWE-ID: CWE-601
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
authlib
authlib
Software vendor:
Authlib
Authlib
Description
The vulnerability allows a remote attacker to redirect users to an attacker-controlled URL.
The vulnerability exists due to url redirection to an untrusted site in OpenIDImplicitGrant and OpenIDHybridGrant authorization request validation when processing authorization requests that omit the openid scope. A remote attacker can send a specially crafted authorization request with an attacker-controlled redirect_uri to redirect users to an attacker-controlled URL.
Exploitation requires an authorization server deployment that registers the OIDC Implicit or Hybrid grant types, and user interaction is required.
Remediation
Install security update from vendor's website.