CVE-2026-77366 obsidian-tc tokens can access arbitrary configured vaults
Attackers with valid tokens can access arbitrary Obsidian vaults to read, write, or delete data due to missing vault binding checks.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-77366?
CVE-2026-77366 is a critical missing authorization vulnerability in The-40-Thieves obsidian-tc, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-77366?
2 open source packages ship an affected version, including obsidian-tc.
| Package | Affected | Fixed in |
|---|---|---|
obsidian-tc npm | All versions | 1.3.1 |
obsidian-tc npm | All versions | 1.3.1 |
How do I fix CVE-2026-77366?
Upgrade obsidian-tc to 1.3.1 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-77366 being exploited?
There is no known exploitation of CVE-2026-77366 in the wild and no public exploit code.
Sources
Also known as GHSA-84c9-qqpq-2pq5.