{"id":"CVE-2026-81100","title":"tiger-gh-mcp-server started its MCP HTTP transport without enabling the host allow-list the underlying SDK provides","summary":"tiger-gh-mcp-server started its MCP HTTP transport without enabling the host allow-list the underlying SDK provides. src/httpServer.ts called the shared httpServerFactory helper and never set the DNS-rebinding-protection option, so the t…","severity":"medium","cvss":6.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N","cwe":["CWE-346"],"published":"2026-08-27","updated":"2026-09-23","sourceUpdated":"2026-09-23T17:17:43.453","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-81100","references":[{"url":"https://github.com/timescale/tiger-gh-mcp-server","label":"disclosure@vulncheck.com"},{"url":"https://github.com/timescale/tiger-gh-mcp-server/pull/36","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/timescale-tiger-gh-mcp-server-dns-rebinding-via-disabled-host-header-allow-list","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"epss":0.00216,"epssPercentile":0.10662,"ingestedAt":"2026-08-29T21:42:35.239Z","slug":"CVE-2026-81100","body":"## Overview\n\ntiger-gh-mcp-server started its MCP HTTP transport without enabling the host allow-list the underlying SDK provides. src/httpServer.ts called the shared httpServerFactory helper and never set the DNS-rebinding-protection option, so the transport accepted a request whatever host it named, making the locally reachable GitHub MCP endpoint drivable from a page in a visitor's browser that pointed a name it controlled at the bound address. The fix passes the option explicitly alongside a dependency update; the update alone would not have closed it. The repository has published no release that brackets the fix, so the affected boundary is the commit preceding it.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":37,"depthScoreParts":{"impact":37.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}