Description
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.28, Markdown Preview Enhanced preview-link handling passes a decoded, Markdown-controlled link target to a Windows file-opening helper that invokes child_process.exec with the start command. When a Windows user opens an untrusted Markdown file and clicks a crafted external or unsupported-scheme link, shell metacharacters in the decoded target are interpreted by cmd.exe as command separators, allowing an attacker-selected command to run with the privileges of the current VS Code user. The attack requires one normal preview-link click but does not require malicious workspace configuration, script execution to be enabled, or additional files. This issue is fixed in version 0.8.28.
References7
- github.com/shd101wyy/crossnote/commit/5588ca2121c3da43fe331575d…
- github.com/shd101wyy/crossnote/pull/442
- github.com/shd101wyy/crossnote/releases/tag/0.9.29
- github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/dc…
- github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2318
- github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/…
- github.com/shd101wyy/vscode-markdown-preview-enhanced/security/…
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 38 · as of 11 November 2026
- CWE
- CWE-78
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.