CVE-2026-54702
Received
Received - Intake
Command Injection in Markdown Preview Enhanced Extension
Vulnerability report for CVE-2026-54702, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-14
Last updated on: 2026-10-14
Assigner: GitHub, Inc.
Description
Description
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.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| shd101wyy | vscode-markdown-preview-enhanced | < 0.8.30 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-749 | The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted. |
