Auth bypass in The-40-Thieves Obsidian-Tc
CVE-2026-77361
obsidian-tc is a governed, agent-ready Model Context Protocol server for Obsidian vaults. Prior to 1.3.1, read access-control list (ACL) checks use a lexical vault-relative path while containment checks use the resolved path. An in-vault symlink under an allowed glob that resolves into a denied folder can therefore bypass the read ACL and expose files in the denied folder. Exploitation requires an out-of-band-planted symlink and does not permit an escape from the vault root. Version 1.3.1 fixes the vulnerability by applying ACL checks to the resolved vault-relative path.
Published .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- The-40-Thieves Obsidian-Tc — versions < 1.3.1
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-77361?
- CVE-2026-77361 is a medium-severity vulnerability in The-40-Thieves Obsidian-Tc, classified under Improper Link Resolution Before File Access. CVSS score: 4.7/10. Published 2026-10-13.
- How severe is CVE-2026-77361?
- Medium severity. CVSS v3 base score is 4.7 out of 10.