CVE-2026-49210
Symfony UX: XSS in symfony/ux-live-component via attacker-controlled child component tag
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
Symfony UX is a JavaScript ecosystem for Symfony. From 2.8.0 until 2.36.0 and 3.1.0, Symfony\UX\LiveComponent\Util\ChildComponentPartialRenderer::createHtml() interpolates the client-controlled children[id].tag value from LiveComponentSubscriber and InterceptChildComponentRenderSubscriber directly into HTML as a tag name without escaping or validation, allowing arbitrary HTML, including <script> tags, on any Live Component re-render that contains at least one child component. This issue is fixed in versions 2.36.0 and 3.1.0.
| CWE | CWE-79 |
| Vendor | symfony |
| Product | ux |
| Published | Jul 17, 2026 |
| Last Updated | Jul 17, 2026 |
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Affected Versions
symfony / ux
>= 3.0.0, < 3.1.0 >= 2.8.0, < 2.36.0