CVE-2026-8630

Summary

justhtml before 1.12.0 (versions <= 1.11.0) contains a mutation cross-site scripting (mXSS) vulnerability in the serialization of raw-text elements such as <style> and <script>. When a DOM tree is processed by sanitize_dom() using a custom policy that keeps these elements, text nodes inside them are serialized literally without escaping, allowing attacker-controlled text containing the matching closing tag sequence to break out of the raw-text context and inject arbitrary HTML into the serialized output. The default sanitization policy is not affected because it drops the contents of style and script.

Affected Software

VendorProductVersion RangeStatus
EmilStenstromjusthtml0 < 1.12.0affected
EmilStenstromjusthtml1.12.0unaffected

Weaknesses

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

References