Vulnerability-Lookup

GHSA-C5XX-H28H-F682

Vulnerability from github – Published: 2026-10-23 17:28 – Updated: 2026-10-23 17:28

Summary

obsidian-tc : Symlink read-ACL scope bypass via lexical path checks

Details

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.

Severity

4.7 (Medium)


                  
                    CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "obsidian-tc"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-77361"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-59",
      "CWE-863"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-23T17:28:19Z",
    "nvd_published_at": "2026-10-13T14:17:42Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nACL 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 \u2014 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.\n\n### Patches\nFixed in **1.3.1**. Upgrade to `\u003e= 1.3.1`. ACL enforcement now derives the realpath vault-relative path and feeds a single unified predicate at every site.\n\n### Workarounds\nDo not permit untrusted symlinks inside the vault.",
  "id": "GHSA-c5xx-h28h-f682",
  "modified": "2026-10-23T17:28:19Z",
  "published": "2026-10-23T17:28:19Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-c5xx-h28h-f682"
    },
    {
      "type": "WEB",
      "url": "https://github.com/The-40-Thieves/obsidian-tc/pull/76"
    },
    {
      "type": "WEB",
      "url": "https://github.com/The-40-Thieves/obsidian-tc/commit/c81d1687e2cfec98a0d8bc5038c029f41ea9c920"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/The-40-Thieves/obsidian-tc"
    },
    {
      "type": "WEB",
      "url": "https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/cve-2026-77361"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "obsidian-tc : Symlink read-ACL scope bypass via lexical path checks"
}

CVE-2026-77361 (GCVE-0-2026-77361)

Vulnerability from cvelistv5 – Published: 2026-10-13 14:00 – Updated: 2026-10-16 21:58

Title

obsidian-tc symlink path mismatch bypasses read ACL restrictions

Summary

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.

Severity

4.7 (Medium)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-16 21:57 UTC

CWE

CWE-59 - Improper Link Resolution Before File Access ('Link Following')
CWE-863 - Incorrect Authorization

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 8044 records in the last 180 days details

References

4 references

URL	Tags
https://github.com/The-40-Thieves/obsidian-tc/sec…	x_refsource_CONFIRM
https://github.com/The-40-Thieves/obsidian-tc/pull/76	x_refsource_MISC
https://github.com/The-40-Thieves/obsidian-tc/com…	x_refsource_MISC
https://github.com/The-40-Thieves/obsidian-tc/rel…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
The-40-Thieves	obsidian-tc	Affected: < 1.3.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-77361",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T21:57:59.773123Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-16T21:58:14.281Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "obsidian-tc",
          "vendor": "The-40-Thieves",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.3.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "NONE",
            "baseScore": 4.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-59",
              "description": "CWE-59: Improper Link Resolution Before File Access (\u0027Link Following\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "CWE-863: Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-13T14:00:39.982Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-c5xx-h28h-f682",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/The-40-Thieves/obsidian-tc/security/advisories/GHSA-c5xx-h28h-f682"
        },
        {
          "name": "https://github.com/The-40-Thieves/obsidian-tc/pull/76",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/The-40-Thieves/obsidian-tc/pull/76"
        },
        {
          "name": "https://github.com/The-40-Thieves/obsidian-tc/commit/c81d1687e2cfec98a0d8bc5038c029f41ea9c920",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/The-40-Thieves/obsidian-tc/commit/c81d1687e2cfec98a0d8bc5038c029f41ea9c920"
        },
        {
          "name": "https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/The-40-Thieves/obsidian-tc/releases/tag/v1.3.1"
        }
      ],
      "source": {
        "advisory": "GHSA-c5xx-h28h-f682",
        "discovery": "UNKNOWN"
      },
      "title": "obsidian-tc symlink path mismatch bypasses read ACL restrictions"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-77361",
    "datePublished": "2026-10-13T14:00:39.982Z",
    "dateReserved": "2026-08-20T19:28:35.245Z",
    "dateUpdated": "2026-10-16T21:58:14.281Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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