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1 vulnerability by marko-js

CVE-2026-41591 (GCVE-0-2026-41591)

Vulnerability from cvelistv5 – Published: 2026-05-08 15:22 – Updated: 2026-05-08 21:26
VLAI?
Title
Marko: XSS via case-insensitive script/style closing tag bypass in runtime HTML escaping
Summary
Marko is a declarative, HTML-based language for building web apps. Prior to marko version 5.38.36 and prior to @marko/runtime-tags 6.0.164, when dynamic text is interpolated into a <script> or <style> tag the Marko runtime failed to prevent tag breakout when the closing tag used non-lowercase casing. An attacker able to place input inside a <script> or <style> block could break out of the tag with </SCRIPT>, </Style>, etc. and inject arbitrary HTML/JavaScript, resulting in cross-site scripting. This issue has been patched in marko version 5.38.36 and @marko/runtime-tags 6.0.164.
Severity ?
6.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
marko-js marko Affected: marko < 5.38.36
Affected: @marko/runtime-tags < 6.0.164
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