CVE-2026-81099 (GCVE-0-2026-81099)
Vulnerability from cvelistv5 – Published: 2026-08-27 14:50 – Updated: 2026-08-29 11:48
VLAI
EPSS
VEX
Title
Timescale tiger-slack DNS Rebinding via Disabled Host Header Allow-List
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-27 17:53 UTC
CWE
- CWE-346 - Origin Validation Error
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/timescale/tiger-slack | product |
| https://github.com/timescale/tiger-slack/pull/146 | issue-trackingpatch |
| https://www.vulncheck.com/advisories/timescale-ti… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| timescale | tiger-slack |
Unaffected:
23faf7ee7e7f73e5ea4f67e627c1aca94bba1f09
(git)
Affected: 0 , < 23faf7ee7e7f73e5ea4f67e627c1aca94bba1f09 (git) |
guessed |
Date Public
2026-08-26 00:00
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