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.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:20

Updated : 2026-08-27 20:18

NVD link : CVE-2026-81099

Mitre link : CVE-2026-81099

CVE.ORG link : CVE-2026-81099

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

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