CVE-2026-81099
tiger-slack started its MCP HTTP transport without enabling the host allow-list the underlying SDK provides. mcp/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, and a page in a browser could point a name it controlled at the address the server was bound to and drive the locally reachable Slack MCP server through the visitor's browser. The fix passes the option explicitly alongside a dependency update; the update alone would not have closed it. The repository publishes no release that brackets the fix, so the affected boundary is the commit preceding it.
- Score
- CVSS 4.0 7.6 High
- Status
- Deferred - disclosure@vulncheck.com
- Published
- 2026-08-27
- Last modified
- 2026-08-29
- Weaknesses
- CWE-346
Affected products
References
- https://github.com/timescale/tiger-slack
- https://github.com/timescale/tiger-slack/pull/146
- https://www.vulncheck.com/advisories/timescale-tiger-slack-dns-rebinding-via-disabled-host-header-allow-list
