Related Vulnerabilities: CVE-2021-22903  

There is a possible Open Redirect Vulnerability in Action Pack 6.1 before version 6.1.3.2. Specially crafted Host headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website.

Severity Medium

Remote Yes

Type Open redirect

Description

There is a possible Open Redirect Vulnerability in Action Pack 6.1 before version 6.1.3.2. Specially crafted Host headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website.

AVG-1919 gitlab 13.10.4-1 Medium Not affected

https://www.openwall.com/lists/oss-security/2021/05/05/2