MEDIUMVulnerability
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.
Properties
- severity
- MEDIUM
- score
- 6.8
- cve_id
- CVE-2026-81099
- signal_observed_at
- 2026-09-23T22:44:39+00:00
- vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
- published_at
- 2026-08-27T17:20:52.467
- last_modified
- 2026-09-23T17:17:42.577
Related Entities (2)
HAS_WEAKNESS (1)
→[Weakness]Origin Validation Error
DESCRIBED_BY (1)
→[Source]NVD
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