๐Ÿ” CVE Alert

CVE-2026-8630

MEDIUM 6.1

justhtml before 1.12.0 Mutation XSS via Raw Text Elements

CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-79
Vendor emilstenstrom
Product justhtml
Published Aug 23, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

Affected Versions

EmilStenstrom / justhtml
0 < 1.12.0

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-qvc2-mg72-jjhx vulncheck.com: https://www.vulncheck.com/advisories/justhtml-before-mutation-xss-via-raw-text-elements

Credits

๐Ÿ” offset