CVE-2026-49493 (GCVE-0-2026-49493)
Vulnerability from cvelistv5
Published
2026-06-05 17:49
Modified
2026-06-09 14:36
Severity ?
8.6 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
Summary
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
Impacted products
Vendor Product Version
shd101wyy Markdown Preview Enhanced Version: 0   ≤
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