VulnerabilityAnalyzed

CVE-2026-49212

From 2.8.0 until 2.36.0 and 3.1.0, the HMAC computed by Symfony\UX\LiveComponent\LiveComponentHydrator covered only sorted prop key/value pairs and did not include the component name, the slot identifier (props vs propsFromParent), or request context,…

MEDIUM 6.9EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

Symfony UX is a JavaScript ecosystem for Symfony. From 2.8.0 until 2.36.0 and 3.1.0, the HMAC computed by Symfony\UX\LiveComponent\LiveComponentHydrator covered only sorted prop key/value pairs and did not include the component name, the slot identifier (props vs propsFromParent), or request context, allowing a signed blob minted for one component or slot to be replayed in another and set a read-only prop on a target component. This issue is fixed in versions 2.36.0 and 3.1.0.

CVSS 4.0: 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.24% probability · 15th percentile
CISA KEV: Not listed
Weakness: CWE-345
Affected: symfony/ux
Source: security-advisories@github.com

References

https://github.com/symfony/ux/commit/a224b5af3e2e33ee14ac71356ae0e0877900a81cPatch
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-34w5-c283-j9fgVendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.