CVE Catalog

CVE-2026-49215

MediumCVSS 5.4
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.18%

8th percentile - higher than 8% of all known CVEs

Summary

A vulnerability in Symfony UX allows CSRF attacks on LiveComponent components. The protection mechanism relies on the Accept header, which can be set by an attacker in a cross-origin request without preflight, enabling unauthorized actions on a victim's session.

Risk Assessment

An attacker can exploit this flaw to perform unauthorized operations on a user's account if the application uses SameSite=None cookies, credentials: 'include', or a permissive cookie policy. This could lead to data theft, content modification, or privilege escalation.

Recommendation

Immediately update Symfony UX to version 2.36.0 or 3.1.0. Additionally, consider strengthening cookie policies (SameSite=Lax/Strict) and implementing additional CSRF mechanisms (e.g., tokens).

Other vulnerabilities in Symfony UX

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS