CVE-2026-49210

LOW
INFO Priority: 0.01 BB Relevance: 55/100
Published: 2026-07-17 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: Present
VC: None
VI: None
VA: None

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.

Weakness Classification (1)

Affected Software (2)

VendorProductVersion
symfony ux 2.8.0 – 2.36.0
symfony ux 3.0.0

Bug Bounty Relevance

55 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

2.3 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.34%
Raw Score 0.003380
Percentile 27.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00338
2026-10-28
0.00338

Intelligence Sources

nvd ref →