Privileged command execution via unchecked webview dispatch
Published Oct 14, 2026 · Updated Oct 14, 2026
Unchecked command dispatch in Markdown Preview Enhanced before 0.8.30 allows attackers to invoke privileged commands via webview messages. The handler in src/preview-provider.ts passes attacker-selected command names and arguments to vscode.commands.executeCommand in the _crossnote namespace without an allowlist or type validation. Exploitation requires JavaScript already executing in the preview webview through a separate injection path; the bridge then exposes file modification, code-chunk execution, export-tool execution, and arbitrary URL opening under the extension host's permissions.
Summary
What happened
Unchecked command dispatch in Markdown Preview Enhanced before 0.8.30 allows attackers to invoke privileged commands via webview messages. The handler in src/preview-provider.ts passes attacker-selected command names and arguments to vscode.commands.executeCommand in the _crossnote namespace without an allowlist or type validation. Exploitation requires JavaScript already executing in the preview webview through a separate injection path; the bridge then exposes file modification, code-chunk execution, export-tool execution, and arbitrary URL opening under the extension host's permissions.
The record
- CVE
- CVE-2026-54702
- Published
- Oct 14, 2026
- Updated
- Oct 14, 2026
- Vendor
- shd101wyy
- Product
- Markdown Preview Enhanced
- Classifications
- CWE-749, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 14, 2026CVE publishedPublication date reported by the CVE source.
- Oct 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 0.8.30
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
- Upstream webview command-dispatch proof of conceptproof of concept · unverified
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started