CVE-2026-49215 Symfony UX: CSRF Protection Bypass in symfony/ux-live-component — Accept Header is CORS-Safelisted
Attackers can bypass CSRF protection in Symfony UX LiveComponent via CORS-safelisted headers, enabling forged cross-origin actions against victim sessions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-49215?
CVE-2026-49215 is a low-severity vulnerability in symfony ux, published on 17 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-352
Which versions are affected by CVE-2026-49215?
4 open source packages ship an affected version, including symfony/ux-live-component. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
symfony/ux-live-component Packagist | From 2.22.0 | 2.36.0 |
symfony/ux-live-component Packagist | From 2.22.0 | 2.36.0 |
symfony/ux-live-component Packagist | From 3.0.0 | 3.1.0 |
symfony/ux-live-component Packagist | From 3.0.0 | 3.1.0 |
Products include Symfony Ux.
How do I fix CVE-2026-49215?
Upgrade symfony/ux-live-component to a fixed version for your release line: 2.36.0 or 3.1.0.
Is CVE-2026-49215 being exploited?
There is no known exploitation of CVE-2026-49215 in the wild and no public exploit code.
Other vulnerabilities in symfony ux
- CVE-2026-49208 Symfony UX: Format-less date LiveProps parsed with the permissive DateTime constructor
- CVE-2026-49211 Symfony UX: Information exposure via unescaped LIKE wildcards in EntitySearchUtil
- CVE-2026-49212 Symfony UX: LiveComponentHydrator HMAC checksum lacks component and slot binding
- CVE-2026-55877 Symfony UX: XSS in symfony/ux-icons via unsanitized SVG content in local files and Iconify on-demand responses
- CVE-2026-49209 Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests
Sources
Also known as GHSA-4m4j-hmqq-3gxm.