CVE-2026-41591

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.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/marko-js/marko/security/advisories/GHSA-x9fj-57fh-c8wq
https://github.com/marko-js/marko/security/advisories/GHSA-x9fj-57fh-c8wq

Configurations

No configuration.

History

08 May 2026, 22:16

Type	Values Removed	Values Added
References	~~() https://github.com/marko-js/marko/security/advisories/GHSA-x9fj-57fh-c8wq -~~	() https://github.com/marko-js/marko/security/advisories/GHSA-x9fj-57fh-c8wq -

08 May 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-08 16:16

Updated : 2026-06-17 10:46

NVD link : CVE-2026-41591

Mitre link : CVE-2026-41591

CVE.ORG link : CVE-2026-41591

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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