PT-2026-51049 · Packagist · Symfony/Ux-Live-Component

Published

2026-06-19

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Updated

2026-06-19

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CVE-2026-49208

CVSS v4.0

6.9

Medium

VectorAV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Description

When a #[LiveProp] is typed as a DateTimeInterface and no explicit format is configured, SymfonyUXLiveComponentLiveComponentHydrator::hydrateObjectValue() falls back to new $className($value). The DateTime / DateTimeImmutable constructors accept relative strings such as "now", "tomorrow", or "+10 years", so a writable, format-less date prop can be pushed to an arbitrary point in time by the client. Components that rely on a date prop to gate time-based business logic can be moved past those checks by a frontend payload that no maintainer would consider a valid date.

Resolution

hydrateObjectValue() now parses format-less date props strictly with createFromFormat(DateTimeInterface::RFC3339, ...), matching the format already emitted by dehydrateObjectValue(). Normal round-trips are unaffected; only inputs that aren't valid RFC 3339 are now rejected, which is consistent with how a format-configured prop already behaved.
The patch for this issue is available here for branch 2.x (and forward-ported to 3.x).

Credits

Symfony would like to thank Pascal Cescon for reporting the issue and Hugo Alliaume for providing the fix.

Exploit

Fix

RCE

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Weakness Enumeration

Related Identifiers

CVE-2026-49208
GHSA-89G7-22C8-3J23

Affected Products

Symfony/Ux-Live-Component