CVE-2026-49212

HIGH

Symfony UX: LiveComponentHydrator HMAC checksum lacks component and slot binding

Title source: cna
STIX 2.1

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.

References (4)

Core 4

Scores

CVSS v3 7.5
EPSS 0.0016
EPSS Percentile 5.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-345
Status published
Products (4)
symfony/ux 3.0.0
symfony/ux 2.8.0 - 2.36.0
symfony/ux < 2.36.0
symfony/ux >= 3.0.0, < 3.1.0
Published Jul 17, 2026
Tracked Since Jul 17, 2026