CVE-2026-77361
obsidian-tc symlink path mismatch bypasses read ACL restrictions
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
4.7
obsidian-tc symlink path mismatch bypasses read ACL restrictions
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.
- Record
CVE-2026-77361- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-59, CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-98694
4.7
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.
- Record
EUVD-2026-98694- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-c5xx-h28h-f682
4.7
obsidian-tc : Symlink read-ACL scope bypass via lexical path checks
Impact
ACL checks ran on the lexical vault-relative path while containment used the realpath. An in-vault symlink placed under an allowed glob, whose realpath resolved into a denied folder, passed the read ACL — an intra-vault read-ACL-scope bypass. It requires an out-of-band-planted symlink (no MCP tool creates one) and is not a vault-root escape.
Patches
Fixed in 1.3.1. Upgrade to >= 1.3.1. ACL enforcement now derives the realpath vault-relative path and feeds a single unified predicate at every site.
Workarounds
Do not permit untrusted symlinks inside the vault.
- Record
GHSA-c5xx-h28h-f682- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-59, CWE-863
- Updated
- 2026-11-02
NVD
4.7
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.
- Record
CVE-2026-77361- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-59, CWE-863
- Updated
- 2026-11-02
OSV
4.7
obsidian-tc symlink path mismatch bypasses read ACL restrictions
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.
- Record
CVE-2026-77361- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-59, CWE-863
- Updated
- 2026-11-02
OSVGHSA-c5xx-h28h-f682
4.7
obsidian-tc : Symlink read-ACL scope bypass via lexical path checks
Impact
ACL checks ran on the lexical vault-relative path while containment used the realpath. An in-vault symlink placed under an allowed glob, whose realpath resolved into a denied folder, passed the read ACL — an intra-vault read-ACL-scope bypass. It requires an out-of-band-planted symlink (no MCP tool creates one) and is not a vault-root escape.
Patches
Fixed in 1.3.1. Upgrade to >= 1.3.1. ACL enforcement now derives the realpath vault-relative path and feeds a single unified predicate at every site.
Workarounds
Do not permit untrusted symlinks inside the vault.
- Record
GHSA-c5xx-h28h-f682- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-59, CWE-863
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
obsidian-tcnpm |
before 1.3.1 | 1.3.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-77361 is a medium vulnerability (CVSS 4.7) in The-40-thieves Obsidian-tc, published October 13, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.11%, the 1st percentile. Fixed in obsidian-tc 1.3.1.
References
github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-c5xx-h28h-f682
github.com/The-40-Thieves/obsidian-tc/pull/76
github.com/The-40-Thieves/obsidian-tc/commit/c81d1687e2cfec98a0d8bc5038c029f41ea9c920
github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1
nvd.nist.gov/vuln/detail/cve-2026-77361
github.com/advisories/GHSA-c5xx-h28h-f682
github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77361.json
nvd.nist.gov/vuln/detail/CVE-2026-77361
github.com/The-40-Thieves/obsidian-tc