{"id":"CVE-2026-54701","revision":"bb70a3d0662841d08ae0c038d312c311","records":[{"revision":"bb70a3d0662841d08ae0c038d312c311","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-54701","aliases":[],"title":"Markdown Preview Enhanced: Stored XSS via Unsanitized `.crossnote/head.html` Injection in Webview","description":"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.","state":0,"publishedAt":"2026-10-14T19:11:51.712+00:00","modifiedAt":"2026-10-20T02:01:15.836+00:00","affected":[{"ecosystem":"Vendor product","name":"vscode-markdown-preview-enhanced","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"shd101wyy\",\n                    \"product\": \"vscode-markdown-preview-enhanced\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 0.8.30\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N","score":6.9,"severity":"MEDIUM"}],"references":["https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3","https://github.com/shd101wyy/crossnote/pull/444","https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2323","https://github.com/shd101wyy/crossnote/commit/8c55a2ba3365712a1caa4abeece0383bc2994d48","https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/8bc848b6cbb42b9f35a0f95f7c3bf29b8302970e","https://github.com/shd101wyy/crossnote/releases/tag/0.9.31","https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.30"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-54701","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-54701","identifiers":["CVE-2026-54701"]},"retained":false,"historicalAffected":[]}],"coverage":[]}