GitLab urges users to patch max severity path traversal flaw

CVE-2021-22175 is a server-side request forgery (SSRF, CWE-918) in GitLab's webhook handling that affects all GitLab versions starting from 10.5. It is exploitable when the administrator setting that allows webhook and integration requests to the internal network is enabled, and an unauthenticated attacker can leverage it even on instances where self-registration is disabled, so no account or credentials are required. A successful attack makes the GitLab server issue requests to internal-network destinations, letting the attacker probe or interact with internal-only services reachable from the GitLab host (for example cloud metadata endpoints or internal APIs); the flaw carries a CVSS 3.1 base score of 9.8 with high confidentiality, integrity, and availability impact. Self-managed GitLab deployments running an affected version with internal-network outbound requests enabled are the exposed population, while instances that are not internet-reachable or that keep that setting disabled are not reachable by this unauthenticated attack path. CISA added the flaw to the Known Exploited Vulnerabilities catalog on 2026-02-18, confirming in-the-wild exploitation; EPSS assigns a 53.4% probability of exploitation within 30 days (99th percentile), and related reporting describes coordinated SSRF exploitation involving more than 400 source IPs.

Do: Upgrade self-managed GitLab to a current supported release; the fix shipped in GitLab 13.7.1 (with backports in 13.6.2 and 13.5.4), so any modern release already includes it, and federal agencies must meet BOD 22-01 timelines or discontinue use of unpatched versions. If patching must wait, check whether Admin Area → Settings → Network allows outbound requests to the internal network for web hooks and integrations, and disable that option or restrict the GitLab host's egress to internal ranges as an interim mitigation. Review webhook and GitLab host network logs for unexpected requests to internal services or cloud metadata endpoints (e.g., 169.254.169.254) that would indicate SSRF probing.

CVE-2021-39935 is a server-side request forgery (CWE-918) in GitLab Community Edition and Enterprise Edition that allows unauthorized external users to make the GitLab server issue requests through the CI Lint API. By abusing the server's network position, an attacker can reach internal-only resources such as loopback or private-network services, potentially mapping or accessing internal infrastructure without credentials. All deployments of the affected editions are potentially exposed, with actual risk depending on whether the CI Lint API is reachable by unauthenticated external users. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2026-02-03, indicating known exploitation in the wild, though no public proof-of-concept is known and ransomware use is unconfirmed. EPSS estimates a 35.6% probability of exploitation within 30 days (98th percentile).

Do: Upgrade GitLab CE/EE to the patched release identified in GitLab's security advisory for CVE-2021-39935 (version numbers are not provided in the source data). Until patching is complete, restrict unauthenticated external access to the CI Lint API (e.g., at the reverse proxy or firewall) and review logs for unexpected requests to loopback or internal-network targets originating from CI lint calls. Federal agencies must follow BOD 22-01 remediation timelines following the 2026-02-03 KEV listing; discontinue or isolate use if mitigations are unavailable.

An issue has been discovered in GitLab CE/EE affecting only version 16.0.0. An unauthenticated malicious user can use a path traversal vulnerability to read arbitrary files on the server when an attachment exists in a public project nested within at least five groups.

GitLab EE contains a critical (CVSS 9.9) deserialization flaw (CWE-502) in which an authenticated user with Duo Chat access can pass a specially crafted GraphQL subscription argument that bypasses serialization and performs a server object lookup. Via this bypass, the attacker can obtain Advanced Search instance configurations and the sensitive credentials they contain. Because the attack requires only a low-privileged account with Duo Chat access over the network, with no user interaction, any EE deployment where Duo Chat is enabled is potentially exposed, including both self-managed instances and GitLab.com. Affected versions are EE 18.3 and later before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2. No public proof-of-concept or CISA KEV listing exists for this CVE as of now, though related GitLab flaws disclosed in the same cycle are reportedly drawing internet-wide probing.

Do: Upgrade GitLab EE to 19.3.2, 19.2.6, or 19.1.8 depending on the version track in use. Until patched, restrict Duo Chat access to trusted users or disable it where feasible, and audit logs for unusual GraphQL subscription activity by authenticated Duo Chat users. After upgrading, rotate Advanced Search (Elasticsearch/OpenSearch) credentials and review search cluster configurations for signs of access.