Critical severity · published Oct 12, 2026
CVE-2026-77366
obsidian-tc tokens can access arbitrary configured vaults
9.9
CVSS
0.3%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OB
obsidian-tc · The-40-Thieves
< 1.3.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77366
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77366
x_refsource_CONFIRM
https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-84c9-qqpq-2pq5
x_refsource_MISC
https://github.com/The-40-Thieves/obsidian-tc/pull/72
x_refsource_MISC
https://github.com/The-40-Thieves/obsidian-tc/commit/38b4992e87dc2715564236e1a42d005ab05a0194
x_refsource_MISC
https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1
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