RCE in Shd101wyy Vscode-Markdown-Preview-Enhanced

CVE-2026-54525

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.

Vulnerability class: Command Injection (OS Command Injection)

Published .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54525?
CVE-2026-54525 is a high-severity vulnerability in Shd101wyy Vscode-Markdown-Preview-Enhanced, classified under OS Command Injection. CVSS score: 8.8/10. Published 2026-10-14.
How severe is CVE-2026-54525?
High severity. CVSS v3 base score is 8.8 out of 10.