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.
Scoring
- Severity
- HIGH
- CVSS base score
- 7.6
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
- EPSS probability
- 0.16%
- CWE
- CWE-346
- Published
- 2026-08-27
- Last modified
- 2026-08-29
Affected products
- timescale tiger-slack
- timescale tiger-slack
Weakness type
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