CVE-2026-77363highCWE-1385CWE-346

CVE-2026-77363: high-severity vulnerability in The-40-Thieves obsidian-tc

obsidian-tc Streamable HTTP transport permits cross-origin loopback vault access

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.8epss 0.2%
obsidian-tc is a governed, agent-ready Model Context Protocol server for Obsidian vaults. Prior to 1.3.1, the Streamable HTTP transport does not validate the Host or Origin header or enable DNS-rebinding protection. When the documented loopback configuration uses auth.mode set to none, a malicious web page can send requests to the local MCP endpoint and receive unrestricted vault access through the http-local caller. Version 1.3.1 fixes the vulnerability by enabling host, origin, and DNS-rebinding validation.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
The-40-Thieves · obsidian-tc
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