CVE-2023-3922 is an open redirect vulnerability identified in GitLab, a widely used web-based DevOps lifecycle tool. This vulnerability affects all GitLab versions starting from 8.15 up to but not including 16.2.8, versions from 16.3 up to 16.3.5, and versions from 16.4 up to 16.4.1. The issue allows attackers to hijack certain links and buttons within the GitLab user interface, redirecting users to malicious external websites. This type of vulnerability falls under CWE-601 (URL Redirection to Untrusted Site), where an application accepts a user-controlled input that specifies a link to an external site and redirects the user without proper validation or sanitization. The CVSS v3.1 base score is 3.0, indicating a low severity level. The vector indicates that the attack can be performed remotely (AV:N) but requires low privileges (PR:L) and user interaction (UI:R). The attack complexity is high (AC:H), meaning exploitation is not trivial. The vulnerability does not impact confidentiality or integrity but can affect availability minimally, primarily by tricking users into visiting malicious sites potentially leading to phishing or malware exposure. No known exploits are currently reported in the wild, and no official patch links were provided in the data, although GitLab typically addresses such issues promptly. The vulnerability’s scope is changed (S:C), indicating that the impact crosses security boundaries within the product. Overall, this vulnerability is a classic open redirect flaw that can be leveraged in social engineering attacks to deceive users of GitLab instances into visiting harmful sites under the guise of legitimate GitLab UI elements.

For European organizations using GitLab, this vulnerability poses a risk primarily in the form of social engineering and phishing attacks. Attackers could craft malicious links or manipulate GitLab UI elements to redirect users to fraudulent websites designed to steal credentials, distribute malware, or conduct further attacks. Since GitLab is widely adopted by enterprises and public sector organizations across Europe for source code management and CI/CD pipelines, exploitation could undermine user trust and potentially lead to credential compromise if users are deceived. Although the vulnerability itself does not directly compromise code repositories or internal systems, the indirect effects of successful phishing could lead to broader security incidents. Organizations with large developer teams or those integrating GitLab with other internal tools may face increased risk if attackers leverage this vulnerability to gain initial access or escalate privileges. The low CVSS score reflects limited direct technical impact, but the social engineering vector means that user awareness and operational security are critical. The vulnerability is less likely to cause widespread service disruption but could facilitate targeted attacks against high-value users or administrators within European companies.

European organizations should prioritize upgrading GitLab to the latest patched versions beyond 16.2.8, 16.3.5, or 16.4.1 as applicable, once official patches are released. In the interim, administrators can implement strict URL validation and filtering rules on any reverse proxies or web application firewalls (WAFs) in front of GitLab to detect and block suspicious redirect parameters. Security teams should conduct user training focused on recognizing phishing attempts and suspicious links, especially those appearing to originate from internal tools like GitLab. Monitoring GitLab logs for unusual redirect patterns or unexpected URL parameters can help detect exploitation attempts. Additionally, organizations should enforce multi-factor authentication (MFA) on GitLab accounts to mitigate the risk of credential theft leading to account compromise. Where possible, limiting GitLab UI access to trusted networks or VPNs can reduce exposure. Finally, security teams should stay informed via GitLab security advisories and apply patches promptly once available.