The flaw, tracked as CVE-2024-45409, arises from an issue in the OmniAuth-SAML and Ruby-SAML libraries, which GitLab uses to handle SAML-based authentication.
The vulnerability occurs when the SAML response sent by an identity provider (IdP) to GitLab contains a misconfiguration or is manipulated.
Specifically, the flaw involves insufficient validation of key elements in the SAML assertions, such as the extern_uid (external user ID), which is used to uniquely identify a user across different systems.
An attacker can craft a malicious SAML response that tricks GitLab into recognizing them as authenticated users, bypassing SAML authentication and gaining access to the GitLab instance.
The CVE-2024-45409 flaw impacts GitLab 17.3.3, 17.2.7, 17.1.8, 17.0.8, 16.11.10, and all prior releases of those branches.
The vulnerability occurs when the SAML response sent by an identity provider (IdP) to GitLab contains a misconfiguration or is manipulated.
Specifically, the flaw involves insufficient validation of key elements in the SAML assertions, such as the extern_uid (external user ID), which is used to uniquely identify a user across different systems.
An attacker can craft a malicious SAML response that tricks GitLab into recognizing them as authenticated users, bypassing SAML authentication and gaining access to the GitLab instance.
The CVE-2024-45409 flaw impacts GitLab 17.3.3, 17.2.7, 17.1.8, 17.0.8, 16.11.10, and all prior releases of those branches.
