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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
References 4
https://github.com/The-40-Thieves/obsidian-tc/commit/6428bfe6fdfd43aa7b4b369be3…
security-advisories@github.com
https://github.com/The-40-Thieves/obsidian-tc/pull/74
security-advisories@github.com
https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1
security-advisories@github.com
https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-pqh8-4pj…
security-advisories@github.com