EmilStenstrom justhtml up to 1.11.x DOM Sanitization sanitize_dom cross site scripting

Summaryinfo

A vulnerability was found in EmilStenstrom justhtml up to 1.11.x. It has been declared as problematic. The affected element is the function sanitize_dom of the component DOM Sanitization. The manipulation results in cross site scripting. This vulnerability is cataloged as CVE-2026-8630. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in EmilStenstrom justhtml up to 1.11.x. Affected is the function sanitize_dom of the component DOM Sanitization. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-8630 since 05/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

Upgrading to version 1.12.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• EmilStenstrom

Name

• justhtml

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11

Website

• Product: https://github.com/EmilStenstrom/justhtml/

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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