{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "source": "REFERENCES"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "e4890d64502e53b717cce0cb73f1a78b244dc640"
            }
          ],
          "repo": "https://github.com/shd101wyy/crossnote",
          "type": "GIT"
        },
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.8.29"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0d4010988c6ae56a38c6dec4a7509cbd5a7dcb4c"
            }
          ],
          "repo": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-427h-jhpr-8jch"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-94"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54566.json"
  },
  "details": "Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.29, Markdown Preview Enhanced evaluates repository-controlled .crossnote/config.js and .crossnote/parser.js files with vm.runInNewContext, which does not provide a security boundary from the Node.js host realm. Opening a Markdown file in a malicious repository automatically loads these files, and prototype-chain traversal can reach the host Function constructor and process object, allowing operating-system commands to execute as the victim account without further interaction. Both configuration evaluation and parser-hook evaluation are affected, and the attack does not depend on module-scoped require being available. This issue is fixed in version 0.8.29.",
  "id": "CVE-2026-54566",
  "modified": "2026-10-16T02:31:14.590241210Z",
  "published": "2026-10-14T19:08:43.663Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/shd101wyy/crossnote/releases/tag/0.9.30"
    },
    {
      "type": "WEB",
      "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.29"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54566.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-427h-jhpr-8jch"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54566"
    },
    {
      "type": "FIX",
      "url": "https://github.com/shd101wyy/crossnote/commit/e4890d64502e53b717cce0cb73f1a78b244dc640"
    },
    {
      "type": "FIX",
      "url": "https://github.com/shd101wyy/crossnote/pull/443"
    },
    {
      "type": "FIX",
      "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/0d4010988c6ae56a38c6dec4a7509cbd5a7dcb4c"
    },
    {
      "type": "FIX",
      "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2320"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Markdown Preview Enhanced: Remote Code Execution via VM Sandbox Escape in `.crossnote/config.js` and `.crossnote/parser.js`"
}