CVE-2026-49210

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/symfony/ux/commit/fbc5e9a1bda7e4556be21bb1d970f382760ed9a9	Patch
https://github.com/symfony/ux/releases/tag/v2.36.0	Release Notes
https://github.com/symfony/ux/releases/tag/v3.1.0	Release Notes
https://github.com/symfony/ux/security/advisories/GHSA-38x5-rcv4-xf7x	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:symfony:ux::::::::
	cpe:2.3:a:symfony:ux:3.0.0:::::::*

History

No history.

Information

Published : 2026-07-17 17:17

Updated : 2026-07-20 16:56

NVD link : CVE-2026-49210

Mitre link : CVE-2026-49210

CVE.ORG link : CVE-2026-49210

JSON object : View

Products Affected

symfony

ux

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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