CVE-2026-49493

Markdown Preview Enhanced before 0.8.28 parses Bitfield fenced code blocks with interpretJS(), which evaluates the block content as code via vm.runInNewContext(), allowing arbitrary code execution. A crafted markdown document containing a malicious bitfield code block executes attacker-controlled code on the server side when the document is rendered or exported. Fixed in 0.8.28 by parsing bitfield register definitions with JSON5.parse(), since they are purely data.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/shd101wyy/vscode-markdown-preview-enhanced/releases/tag/0.8.28
https://www.vulncheck.com/advisories/markdown-preview-enhanced-arbitrary-code-execution-via-bitfield-interpretjs

Configurations

No configuration.

History

05 Jun 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-05 18:17

Updated : 2026-06-05 18:59

NVD link : CVE-2026-49493

Mitre link : CVE-2026-49493

CVE.ORG link : CVE-2026-49493

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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