CVE-2025-0605 is a medium-severity vulnerability affecting GitLab Community Edition (CE) and Enterprise Edition (EE) versions from 16.8 up to but not including 17.10.7, 17.11 up to 17.11.3, and 18.0 up to 18.0.1. The vulnerability arises from weak authentication controls related to group access permissions. Specifically, certain users with group access can bypass the enforced two-factor authentication (2FA) requirements intended to secure account access. This bypass undermines the multi-factor authentication mechanism, which is a critical security control designed to prevent unauthorized access even if credentials are compromised. The vulnerability is classified under CWE-1390, which relates to weak authentication mechanisms. The CVSS v3.1 base score is 4.6 (medium), with vector AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N, indicating that the attack can be performed remotely over the network with low attack complexity, requires low privileges (some authenticated access), and user interaction is required. The impact is limited to confidentiality and integrity, with no direct availability impact. No known exploits are currently reported in the wild, and no official patches or fixes are linked yet, though GitLab has acknowledged the issue. This vulnerability could allow an attacker with some level of group access to circumvent 2FA protections, potentially gaining unauthorized access to sensitive project repositories, codebases, or internal configurations, which could lead to data leakage or unauthorized code changes.

For European organizations, especially those relying on GitLab for source code management and CI/CD pipelines, this vulnerability poses a significant risk to the confidentiality and integrity of their software development lifecycle. Bypassing 2FA could allow attackers to impersonate legitimate users, access private repositories, and potentially inject malicious code or exfiltrate intellectual property. This risk is heightened in sectors with strict regulatory requirements such as finance, healthcare, and critical infrastructure, where unauthorized access could lead to compliance violations and reputational damage. Additionally, organizations with collaborative projects involving multiple users and groups are particularly vulnerable, as the group access control weakness directly affects multi-user environments. The absence of known exploits reduces immediate risk but does not eliminate the threat, as attackers may develop exploits once the vulnerability details become widely known. The medium CVSS score suggests moderate urgency, but the potential for lateral movement within organizations and the criticality of source code integrity elevate the importance of timely mitigation.

European organizations should immediately audit their GitLab instances to identify affected versions and prioritize upgrading to the fixed versions beyond 17.10.7, 17.11.3, or 18.0.1 as soon as they become available. Until patches are applied, organizations should enforce stricter access controls by limiting group membership to trusted users only and reviewing group permissions to minimize exposure. Implement compensating controls such as IP allowlisting for GitLab access, enhanced monitoring and alerting on authentication anomalies, and mandatory use of hardware-based 2FA tokens where possible. Additionally, organizations should conduct internal penetration testing focusing on authentication bypass scenarios and review audit logs for suspicious access patterns. It is also advisable to educate users about the risk of 2FA bypass and encourage vigilance regarding unexpected authentication prompts or access. Finally, organizations should stay informed through GitLab security advisories and subscribe to vulnerability feeds to promptly respond to any new developments or patches.