Vulnerability · CVE-2026-54703
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code.
Published Oct 14, 2026 · catalog updated Oct 15, 2026 · Markdown Preview Enhanced is
Check if you run it
No confirmed exploitation is on record for CVE-2026-54703. EPSS is 0.22%. Act only if a listed version of Markdown Preview Enhanced is is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (Markdown Preview Enhanced is).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium5.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.22%
- Remediation
- Advisory link
- Affected products
- See sources for product scope
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the _crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile without validating that the target is the Markdown file represented by the current preview. JavaScript already executing in the preview webview can invoke this command through the extension message bridge and write any file permitted by the VS Code user's operating-system privileges, including user configuration, startup, source, and build files. This file-write vulnerability requires a separate webview JavaScript execution path, such as the independently tracked head.html injection and blind command-dispatch weaknesses. This issue is fixed in version 0.8.30.
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix CVE-2026-54703
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-54703. EPSS is 0.22%. Act only if a listed version of Markdown Preview Enhanced is is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-73. EPSS 0.22%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Oct 14, 2026 · NIST NVD
Detected
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the _crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile without validating that the target is the Markdown file represented by the current preview. JavaScript already executing in th
Oct 15, 2026 · NIST NVD
Updated
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the _crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile without validating that the target is the Markdown file represented by the current preview. JavaScript already executing in th
Sources
- CVE.orgVulnerability recordCVE-2026-54703
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-54703
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2026-54703
Markdown Preview Enhanced is a Markdown preview extension for Visual Studio Code. Prior to 0.8.30, the _crossnote.updateMarkdown command in Markdown Preview Enhanced accepts an arbitrary URI and attacker-controlled content, then passes them to vscode.workspace.fs.writeFile withou
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.