CVE-2026-49210
Full vulnerability record from the local CVENow database.
Description
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.
Severity
LOW
CVSS score
2.3
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-17 17:17:15.650000
Last modified
2026-10-24 20:10:00.137000
View original CVE JSON
{
"id": "CVE-2026-49210",
"sourceIdentifier": "[email protected]",
"published": "2026-07-17T17:17:15.650",
"lastModified": "2026-10-24T20:10:00.137",
"vulnStatus": "Analyzed",
"cveTags": [],
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"value": "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."
},
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"lang": "es",
"value": "Symfony UX es un ecosistema de JavaScript para Symfony. Desde 2.8.0 hasta 2.36.0 y 3.1.0, Symfony\\UX\\LiveComponent\\Util\\ChildComponentPartialRenderer::createHtml() interpola el valor children[id].tag controlado por el cliente de LiveComponentSubscriber y InterceptChildComponentRenderSubscriber directamente en HTML como un nombre de etiqueta sin escape ni validación, permitiendo HTML arbitrario, incluyendo etiquetas [script_tag], en cualquier re-renderización de Live Component que contenga al menos un componente hijo. Este problema está solucionado en las versiones 2.36.0 y 3.1.0."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "symfony",
"product": "ux",
"versions": [
{
"version": ">= 3.0.0, < 3.1.0",
"status": "affected"
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"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
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"weaknesses": [
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"type": "Primary",
"description": [
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"source": "[email protected]",
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{
"url": "https://github.com/symfony/ux/security/advisories/GHSA-38x5-rcv4-xf7x",
"source": "[email protected]",
"tags": [
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}