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TI-2026-36411 Aliases CVE-2026-49210GHSA-38x5-rcv4-xf7x

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

Priority LOW 12CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
Present
Impact type
Cross-site scripting
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00338 27th percentileScored 2026-11-07
Fix Fixed ux (symfony): 3.1.0, 2.36.0symfony/ux-live-component (Packagist): 2.36.0, 3.1.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
symfonyux3.0.0 to before 3.1.0; 2.8.0 to before 2.36.03.1.0, 2.36.0Patch availableCNA
—symfony/ux-live-component (Packagist)2.8.0 to before 2.36.02.36.0Patch availableGHSA-38x5-rcv4-xf7x
—symfony/ux-live-component (Packagist)3.0.0 to before 3.1.03.1.0Patch availableGHSA-38x5-rcv4-xf7x
  • ux Vendorsymfony Affected 3.0.0 to before 3.1.0; 2.8.0 to before 2.36.0 Fixed in 3.1.0, 2.36.0 Patch available CNA
  • symfony/ux-live-component (Packagist) Vendor— Affected 2.8.0 to before 2.36.0 Fixed in 2.36.0 Patch available GHSA-38x5-rcv4-xf7x
  • symfony/ux-live-component (Packagist) Vendor— Affected 3.0.0 to before 3.1.0 Fixed in 3.1.0 Patch available GHSA-38x5-rcv4-xf7x

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:symfony:ux:*:*:*:*:*:*:*:*2.8.0 to before 2.36.0Vulnerablesymfony
cpe:2.3:a:symfony:ux:3.0.0:*:*:*:*:*:*:*3.0.0Vulnerablesymfony
  • cpe:2.3:a:symfony:ux:*:*:*:*:*:*:*:* Versions 2.8.0 to before 2.36.0 Vulnerable ·symfony
  • cpe:2.3:a:symfony:ux:3.0.0:*:*:*:*:*:*:* Versions 3.0.0 Vulnerable ·symfony

Remediation

  • Fix · CNA ux (symfony) Fixed in 3.1.0, 2.36.0
  • Fix · GHSA-38x5-rcv4-xf7x symfony/ux-live-component (Packagist) Fixed in 2.36.0 Advisory →
  • Fix · GHSA-38x5-rcv4-xf7x symfony/ux-live-component (Packagist) Fixed in 3.1.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49210
  2. 2026-10-03 Alias added: GHSA-38x5-rcv4-xf7x

References

Patch 1

Advisory 1

Other 4

  • TI-2026-36412 Symfony UX: Information exposure via unescaped LIKE wildcards in EntitySearchUtil CVSS 4.0MEDIUM 6.9
  • TI-2026-36409 Symfony UX: Format-less date LiveProps parsed with the permissive DateTime constructor CVSS 4.0MEDIUM 6.9
  • TI-2026-36413 Symfony UX: LiveComponentHydrator HMAC checksum lacks component and slot binding CVSS 4.0MEDIUM 6.9
  • TI-2026-40330 Symfony UX: XSS in symfony/ux-icons via unsanitized SVG content in local files and Iconify on-demand responses CVSS 3.1MEDIUM 6.1
  • TI-2026-36410 Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests CVSS 4.0MEDIUM 5.3
  • TI-2026-36417 Symfony UX: XSS in symfony/ux-autocomplete via unescaped AJAX response data CVSS 4.0MEDIUM 5.1
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences