{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-54701",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-15T22:58:06.563Z",
        "datePublished": "2026-10-14T19:11:51.712Z",
        "dateUpdated": "2026-10-14T19:11:51.712Z"
    },
    "containers": {
        "cna": {
            "title": "Markdown Preview Enhanced: Stored XSS via Unsanitized `.crossnote/head.html` Injection in Webview",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-79",
                            "lang": "en",
                            "description": "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "LOCAL",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "LOW",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "LOW",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 6.9,
                        "baseSeverity": "MEDIUM",
                        "vectorString": "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",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3"
                },
                {
                    "name": "https://github.com/shd101wyy/crossnote/pull/444",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/crossnote/pull/444"
                },
                {
                    "name": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2323",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2323"
                },
                {
                    "name": "https://github.com/shd101wyy/crossnote/commit/8c55a2ba3365712a1caa4abeece0383bc2994d48",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/crossnote/commit/8c55a2ba3365712a1caa4abeece0383bc2994d48"
                },
                {
                    "name": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/8bc848b6cbb42b9f35a0f95f7c3bf29b8302970e",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/8bc848b6cbb42b9f35a0f95f7c3bf29b8302970e"
                },
                {
                    "name": "https://github.com/shd101wyy/crossnote/releases/tag/0.9.31",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/crossnote/releases/tag/0.9.31"
                },
                {
                    "name": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.30",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.30"
                }
            ],
            "affected": [
                {
                    "vendor": "shd101wyy",
                    "product": "vscode-markdown-preview-enhanced",
                    "versions": [
                        {
                            "version": "< 0.8.30",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-10-14T19:11:51.712Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "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."
                }
            ],
            "source": {
                "advisory": "GHSA-mcwg-4j78-qwv3",
                "discovery": "UNKNOWN"
            }
        }
    }
}