{"id":"CVE-2026-61559","sourceIdentifier":"security-advisories@github.com","published":"2026-09-15T21:16:41.390","lastModified":"2026-09-30T17:51:56.193","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"`@zereight/mcp-gitlab` is a Model Context Protocol server for GitLab. Starting in version 0.0.1 and prior to version 2.1.27, when the environment variable `ENABLE_DYNAMIC_API_URL=true` is set, the server reads the `X-GitLab-API-URL` HTTP request header and uses it as the base URL for all outbound GitLab API calls made within that request. The server validates that the value is a well-formed URL (`new URL(dynamicApiUrl)`) but applies no allowlist or hostname restriction. The server then attaches the victim's `Private-Token` to every outbound fetch that uses the redirected URL. Any caller who can reach the HTTP transport can set `X-GitLab-API-URL` to an attacker-controlled host. The next GitLab API call the server makes delivers the victim's token to that host. Version 2.1.27 contains a patch."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"zereight","product":"gitlab-mcp","versions":[{"version":">= 0.0.1, < 2.1.27","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N","baseScore":9.6,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":3.1,"impactScore":5.8}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-17T16:49:44.156114Z","id":"CVE-2026-61559","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-918"}]}],"references":[{"url":"https://github.com/zereight/gitlab-mcp/commit/6ffb4cc70706fd05b1ab80901676bc2998b6db6d","source":"security-advisories@github.com"},{"url":"https://github.com/zereight/gitlab-mcp/pull/625","source":"security-advisories@github.com"},{"url":"https://github.com/zereight/gitlab-mcp/releases/tag/v2.1.27","source":"security-advisories@github.com"},{"url":"https://github.com/zereight/gitlab-mcp/security/advisories/GHSA-2h44-8472-frjj","source":"security-advisories@github.com"},{"url":"https://github.com/zereight/gitlab-mcp/security/advisories/GHSA-2h44-8472-frjj","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}