CVE-2026-41591
6.4 · MEDIUMOverview
CVE-2026-41591 is a medium-severity vulnerability affecting openjsf marko. It was published on May 8, 2026 and has a CVSS 3.1 base score of 6.4 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from openjsf. Update marko to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| openjsf | marko | >= 0, < 5.38.36 | Affected |
| openjsf | marko\/runtime-tags | >= 0, < 6.0.164 | Affected |
Frequently Asked Questions
What is CVE-2026-41591?
CVE-2026-41591 is a medium-severity vulnerability affecting openjsf marko. It was published on May 8, 2026 and has a CVSS 3.1 base score of 6.4 (MEDIUM).
How severe is CVE-2026-41591?
This vulnerability has a CVSS 3.1 base score of 6.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-41591?
Check the references section for vendor advisories and patches from openjsf. Update marko to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-41591?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-41591 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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