# CVE-2026-81100: Timescale tiger-gh-mcp-server DNS Rebinding via Disabled Host Header Allow-List

> CVE-2026-81100: Timescale tiger-gh-mcp-server DNS Rebinding via Disabled Host Header Allow-List. CVSS 6.8 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-81100
Last updated: 2026-09-23T17:17:43Z

- Published: 2026-08-27 14:50 UTC · Updated: 2026-09-23 17:17 UTC · Assigner: VulnCheck
- CVSS: 6.8 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
- EPSS: 0.22%, 12th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-346

## Description

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.

## Affected vendors and products

- timescale: tiger-gh-mcp-server

## Tracked companies

- [Timescale (Tiger Data)](https://rewindex.com/company/timescale-tiger-data.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-81100)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-81100)
- [https://github.com/timescale/tiger-gh-mcp-server](https://github.com/timescale/tiger-gh-mcp-server)
- [https://github.com/timescale/tiger-gh-mcp-server/pull/36](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](https://www.vulncheck.com/advisories/timescale-tiger-gh-mcp-server-dns-rebinding-via-disabled-host-header-allow-list)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-81100 · Markdown: https://rewindex.com/cve/CVE-2026-81100.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-81100 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:13:03.848Z