---
title: "CVE-2026-77366: obsidian-tc tokens can access arbitrary configured vaults"
url: https://erroneo.us/security/cve/CVE-2026-77366/
description: "CVE-2026-77366 (obsidian-tc (npm)): obsidian-tc is a governed, agent-ready Model Context Protocol server for Obsidian vaults. Prior to 1.3.1, tool dispatch…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-10-12
date_modified: 2026-10-23
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-77366"
kev: false
cvss: 9.9
epss: 0.00308
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-77366: obsidian-tc tokens can access arbitrary configured vaults

**Signal:** Critical, preconditions apply. Severe if exploited, but exploitation needs conditions that may not apply to you. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.3% , percentile 22: FIRST’s model estimates a 0.3% chance of exploitation activity in the next 30 days, higher than 22% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes obsidian-tc (npm) < 1.3.1, fixed in 1.3.1 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- npm `obsidian-tc` < 1.3.1 → fixed: 1.3.1

## Affected products (CVE record)

- The-40-Thieves obsidian-tc: < 1.3.1

## Severity

- GitHub_M CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-23): 0.31% probability of exploitation activity in the next 30 days; percentile 22.

## Sources

- [GitHub Advisory GHSA-84c9-qqpq-2pq5](https://github.com/advisories/GHSA-84c9-qqpq-2pq5)
- [CVE.org record CVE-2026-77366](https://www.cve.org/CVERecord?id=CVE-2026-77366)
- [NVD entry CVE-2026-77366](https://nvd.nist.gov/vuln/detail/CVE-2026-77366)
- [github.com](https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-84c9-qqpq-2pq5)
- [github.com](https://github.com/The-40-Thieves/obsidian-tc/pull/72)
- [github.com](https://github.com/The-40-Thieves/obsidian-tc/commit/38b4992e87dc2715564236e1a42d005ab05a0194)
- [github.com](https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1)
- [nvd.nist.gov](https://nvd.nist.gov/vuln/detail/cve-2026-77366)

---
Source page: https://erroneo.us/security/cve/CVE-2026-77366/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt