CVE-2026-54701: shd101wyy vscode-markdown-preview-enhanced · Cross-site Scripting
Affects shd101wyy vscode-markdown-preview-enhancedSource CVE Database V5
Not known to be exploited · CVSS 6.9 Medium : upgrade to 0.8.30 when convenient.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.8.30
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade vscode-markdown-preview-enhanced and shd101wyy/vscode-markdown-preview-enhanced to 0.8.30.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| shd101wyyvscode-markdown-preview-enhanced | Affected
| Fixed in
|
GitHubshd101wyy/vscode-markdown-preview-enhancedpkg:github/shd101wyy/vscode-markdown-preview-enhancedOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade vscode-markdown-preview-enhanced to version 0.8.30 or later, where this vulnerability is fixed. No other mitigation is required as the fix addresses the root cause by properly sanitizing the inserted content.
Description
Markdown Preview Enhanced for Visual Studio Code versions prior to 0.8.30 contains a cross-site scripting (XSS) vulnerability. The extension reads repository-controlled .crossnote/head.html content and inserts it into the preview webview's head without removing executable script content. This allows script execution before React and DOMPurify initialize, enabling malicious scripts to run when opening a Markdown preview in a malicious repository without further user interaction. The issue is fixed in version 0.8.30.
References
- github.com/shd101wyy/vscode-markdown-preview-enhanced/security/advisories/GHSA-mcwg-4j78-qwv3 (opens in a new tab)
- github.com/shd101wyy/crossnote/pull/444 (opens in a new tab)
- github.com/shd101wyy/vscode-markdown-preview-enhanced/pull/2323 (opens in a new tab)
- github.com/shd101wyy/crossnote/commit/8c55a2ba3365712a1caa4abeece0383bc2994d48 (opens in a new tab)
- github.com/shd101wyy/vscode-markdown-preview-enhanced/commit/8bc848b6cbb42b9f35a0f95f7c3bf29b8302970e (opens in a new tab)
- github.com/shd101wyy/crossnote/releases/tag/0.9.31 (opens in a new tab)
- github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.30 (opens in a new tab)