CVE-2023-0632 is a vulnerability identified in GitLab versions starting from 15.2 up to but not including 16.0.8, versions from 16.1.0 up to 16.1.3, and versions from 16.2.0 up to 16.2.2. The issue is classified as CWE-1333, which relates to inefficient regular expression complexity leading to a Regular Expression Denial of Service (ReDoS). This vulnerability arises when GitLab processes crafted payloads during searches against the Harbor Registry, a container image registry integrated with GitLab. The crafted input exploits inefficient regular expression patterns, causing excessive CPU consumption and potentially rendering the GitLab service unresponsive or significantly degraded. The CVSS v3.1 base score is 6.5 (medium severity), with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), but high impact on availability (A:H). No known exploits are reported in the wild yet, and no patch links are provided in the data, but GitLab has reserved the CVE and published the vulnerability details. The vulnerability specifically affects the search functionality interacting with Harbor Registry, which is commonly used for container image management within GitLab CI/CD pipelines and DevOps workflows.

For European organizations, the impact of this vulnerability can be significant, especially for those relying heavily on GitLab for source code management, CI/CD pipelines, and container registry integration. A successful ReDoS attack can cause denial of service by exhausting server resources, leading to downtime or degraded performance of GitLab services. This can disrupt development workflows, delay software releases, and impact operational continuity. Since the vulnerability requires low attack complexity and can be exploited remotely over the network with only low privileges, it poses a risk even from internal threat actors or compromised accounts. The lack of impact on confidentiality and integrity reduces the risk of data breaches but availability loss can still cause operational and financial damage. Organizations in sectors with stringent uptime requirements, such as finance, healthcare, and critical infrastructure, may face compliance and regulatory challenges if service disruptions occur. Additionally, the integration with Harbor Registry means containerized application deployments could be indirectly affected, impacting cloud-native environments prevalent in European enterprises.

European organizations should prioritize upgrading GitLab to versions 16.0.8, 16.1.3, or 16.2.2 and later, where the vulnerability is patched. Until patches are applied, organizations can mitigate risk by restricting access to the GitLab Harbor Registry search functionality to trusted users only, employing network segmentation and firewall rules to limit exposure. Monitoring GitLab logs for unusual or repetitive search queries that could indicate exploitation attempts is advisable. Rate limiting search requests and implementing Web Application Firewall (WAF) rules to detect and block malicious payloads targeting regular expression processing can reduce attack surface. Additionally, organizations should review and tighten privileges to ensure only necessary users have access to search features requiring low privileges. Regularly auditing GitLab configurations and keeping up with vendor advisories will help maintain security posture. For containerized environments, isolating Harbor Registry access and enforcing strict authentication and authorization policies further reduce risk.