Vulnerability in Markdown Preview Enhanced (CVE-2026-54702)
Summary
Vulnerability in Markdown Preview Enhanced (CVE-2026-54702). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the webview message handler in src/preview-provider.ts accepts an attacker-controlled command value and attacker-controlled args, constructs a command in the _crossnote namespace, and invokes vscode.commands.executeCommand without an allowlist or type validation. JavaScript already executing in the preview webview can use this bridge to invoke privileged extension commands, including file modification, code-chunk execution, export-tool execution, and arbitrary URL opening, with attacker-selected arguments. Exploitation requires a separate webview JavaScript execution path, such as the independently tracked .crossnote/head.html injection, but no further authorization check protects the extension-host command boundary. This issue is fixed in version 0.8.30.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-54702 has been found in Markdown Preview Enhanced.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Markdown Preview Enhanced CVE-2026-54702" on the vendor's site.
CVE-2026-54702 (Markdown Preview Enhanced) — CWE-749
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-749) exists in Markdown Preview Enhanced.
Check the vendor advisory for the affected versions of Markdown Preview Enhanced.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Markdown Preview Enhanced を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。