CVE-2026-81100

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 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.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/timescale/tiger-gh-mcp-server
https://github.com/timescale/tiger-gh-mcp-server/pull/36
https://www.vulncheck.com/advisories/timescale-tiger-gh-mcp-server-dns-rebinding-via-disabled-host-header-allow-list

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:20

Updated : 2026-08-29 04:18

NVD link : CVE-2026-81100

Mitre link : CVE-2026-81100

CVE.ORG link : CVE-2026-81100

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

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