CVE-2026-49493

HIGH

Markdown Preview Enhanced Arbitrary Code Execution via Bitfield interpretJS()

Title source: cna
STIX 2.1

Description

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.

References (2)

Core 2
Core References
Third Party Advisory third-party-advisory
VulnCheck Advisory: Markdown Preview Enhanced Arbitrary Code Execution via Bitfield interpretJS()
https://www.vulncheck.com/advisories/markdown-preview-enhanced-arbitrary-code-execution-via-bitfield-interpretjs

Scores

CVSS v3 8.8
EPSS 0.0033
EPSS Percentile 24.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-94
Status published
Products (1)
shd101wyy/Markdown Preview Enhanced < 0.8.28
Published Jun 05, 2026
Tracked Since Jun 06, 2026