Description
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.
Recommendation
Update the @marko/runtime-tags package to the latest compatible version. Followings are version details:
- Affected version(s): < 6.0.164
- Patched version(s): 6.0.164
References
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See something that needs correcting? Let us knowUpdated May 13, 2026