Vulnerability Description
Symfony UX is a JavaScript ecosystem for Symfony. From 2.22.0 until 2.36.0 and 3.1.0, Symfony\UX\LiveComponent\EventListener\LiveComponentSubscriber::isLiveComponentRequest() gates #[LiveAction] invocations on Accept: application/vnd.live-component+html, but the Accept header is CORS-safelisted and cross-origin fetch() can set it without preflight, allowing forged cross-origin #[LiveAction] requests against a victim session when applications use SameSite=None, credentials: 'include', a permissive cookie policy, or a same-origin pivot. This issue is fixed in versions 2.36.0 and 3.1.0.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Symfony | Ux | >= 2.22.0, < 2.36.0 |
Related Weaknesses (CWE)
References
- https://github.com/symfony/ux/commit/aed7493db2b4b7bf1f9c79b33cda544f06904b27Patch
- https://github.com/symfony/ux/releases/tag/v2.36.0Release Notes
- https://github.com/symfony/ux/releases/tag/v3.1.0Release Notes
- https://github.com/symfony/ux/security/advisories/GHSA-4m4j-hmqq-3gxmVendor Advisory
FAQ
What is CVE-2026-49215?
CVE-2026-49215 is a vulnerability with a CVSS score of 5.4 (MEDIUM). Symfony UX is a JavaScript ecosystem for Symfony. From 2.22.0 until 2.36.0 and 3.1.0, Symfony\UX\LiveComponent\EventListener\LiveComponentSubscriber::isLiveComponentRequest() gates #[LiveAction] invoc...
How severe is CVE-2026-49215?
CVE-2026-49215 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-49215?
Check the references section above for vendor advisories and patch information. Affected products include: Symfony Ux.