CVE-2026-77366: critical vulnerability in The-40-Thieves obsidian-tc
obsidian-tc tokens can access arbitrary configured vaults
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.9epss 0.3%
obsidian-tc is a governed, agent-ready Model Context Protocol server for Obsidian vaults. Prior to 1.3.1, tool dispatch does not compare the caller-controlled input.vault value with the vault bound to the caller, the JSON Web Token (JWT) has no vault claim, and the folder access-control list is shared globally. Any valid token can therefore select another configured vault and read, write, or delete its contents through affected tools. Version 1.3.1 fixes the vulnerability by binding tokens and request context to a vault and rejecting mismatched input.vault values before scope checks.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Affected products
The-40-Thieves · obsidian-tcRelated CVEs — The-40-Thieves obsidian-tc
In the same product, most dangerous first.
CVE-2026-115477HIGHobsidian-tc: Declined human-in-the-loop confirmations can permit destructive calls over HTTPEPSS 0.4%CVE-2026-115478HIGHobsidian-tc: Memory-lifecycle tools overwrite unowned notes or partially commit lifecycle changesEPSS 0.3%CVE-2026-77364MEDIUMobsidian-tc fail-open default ACL exposes Obsidian control-directory secretsEPSS 0.2%CVE-2026-77362MEDIUMobsidian-tc bridge tools expose data outside the read ACLEPSS 0.2%CVE-2026-77363HIGHobsidian-tc Streamable HTTP transport permits cross-origin loopback vault accessEPSS 0.2%CVE-2026-77361MEDIUMobsidian-tc symlink path mismatch bypasses read ACL restrictionsEPSS 0.1%
References
https://github.com/The-40-Thieves/obsidian-tc/commit/38b4992e87dc2715564236e1a42d005ab05a0194https://github.com/The-40-Thieves/obsidian-tc/pull/72https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-84c9-qqpq-2pq5