{"id":"CVE-2026-54566","published":"2026-10-14T20:17:47.403","lastModified":"2026-10-16T16:00:33.533","description":"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.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-94"],"vendors":[],"products":[],"references":[{"url":"https://github.com/shd101wyy/crossnote/commit/e4890d64502e53b717cce0cb73f1a78b244dc640","tags":[]},{"url":"https://github.com/shd101wyy/crossnote/pull/443","tags":[]},{"url":"https://github.com/shd101wyy/crossnote/releases/tag/0.9.30","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/0d4010988c6ae56a38c6dec4a7509cbd5a7dcb4c","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2320","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.29","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-427h-jhpr-8jch","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-427h-jhpr-8jch","tags":[]}],"exploitRefs":[{"url":"https://github.com/shd101wyy/crossnote/commit/e4890d64502e53b717cce0cb73f1a78b244dc640","tags":[]},{"url":"https://github.com/shd101wyy/crossnote/pull/443","tags":[]},{"url":"https://github.com/shd101wyy/crossnote/releases/tag/0.9.30","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/0d4010988c6ae56a38c6dec4a7509cbd5a7dcb4c","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2320","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.29","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-427h-jhpr-8jch","tags":[]},{"url":"https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-427h-jhpr-8jch","tags":[]}],"hasPoc":true,"ai":null}