CVE-2026-49210

Symfony UX: XSS in LiveComponent due to ChildComponentPartialRenderer::createHtml() injecting client-controlled children[id].tag into HTML without escaping. Affected: 2.8.0–2.36.0 and 3.1.0. Exploitation potential includes arbitrary HTML, e.g., [removed] tags, on re-renders containing at least on...

CVE-2026-49210 Symfony UX: XSS in symfony/ux-live-component via attacker-controlled child component tag

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 childrenid.tag value from LiveComponentSubscriber and InterceptChildComponentRenderSubscriber directly in...

GHSA-38X5-RCV4-XF7X symfony/ux-live-component: XSS via attacker-controlled child component tag

Description Symfony\UX\LiveComponent\Util\ChildComponentPartialRenderer::createHtml interpolates the $childTag argument directly into the HTML output as a tag name, without escaping or validation. The value originates from client-controlled JSON childrenid.tag parsed by LiveComponentSubscriber an...

symfony/ux-live-component: XSS via attacker-controlled child component tag

Description Symfony\UX\LiveComponent\Util\ChildComponentPartialRenderer::createHtml interpolates the $childTag argument directly into the HTML output as a tag name, without escaping or validation. The value originates from client-controlled JSON childrenid.tag parsed by LiveComponentSubscriber an...

Cross-site Scripting (XSS)

Overview symfony/ux-live-component is a Live components for Symfony Affected versions of this package are vulnerable to Cross-site Scripting XSS via improper handling of child component tag names in ChildComponentPartialRenderer::createHtml. An attacker can inject arbitrary HTML, including...