Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, Markdown Preview Enhanced reads repository-controlled .crossnote/head.html content and passes it through resolvePathsInHeader before inserting it into the head of the preview webview document without removing executable content. Script-capable markup executes while the document loads, before the React application and DOMPurify initialize, and can access acquireVsCodeApi to send messages from the webview to the extension host. Opening a Markdown preview in a malicious repository is sufficient to trigger the injected content, and no additional click within the notification or preview is required. This issue is fixed in version 0.8.30.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 3
- StatusAwaiting Analysis → PublishedNVD modified 2026-10-20 02:01
- StatusReceived → Awaiting AnalysisNVD modified 2026-10-16 16:00
- First seenCVSS 6.9NVD modified 2026-10-14 20:17
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 8
- https://github.com/shd101wyy/crossnote/commit/8c55a2ba3365712a1caa4abeece0383bc2994d48
- https://github.com/shd101wyy/crossnote/pull/444
- https://github.com/shd101wyy/crossnote/releases/tag/0.9.31
- https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/8bc848b6cbb42b9f35a0f95f7c3bf29b8302970e
- https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2323
- https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.30
- https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3
- https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3