CVE-2026-48489: Symfony: Security Firewall Bypass via failure_forward Subrequest: Unauthenticated Access to access_control-Protected GET Routes

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-14 · updated 2026-07-16
Weakness: CWE-863

Description

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.53, 6.4.41, 7.4.13, and 8.0.13, DefaultAuthenticationFailureHandler honored the request-supplied _failure_path parameter when failure_forward: true was enabled, allowing an unauthenticated failing login request to dispatch a subrequest to access_control-protected GET routes that skipped firewall listeners. This issue is fixed in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13.

Affected products

symfony: before 5.4.53; from 6.0.0 before 6.4.41; from 7.0.0 before 7.4.13; from 8.0.0 before 8.0.13 — fixed in 5.4.53, 6.4.41, 7.4.13, 8.0.13

How to fix

Upgrade to a fixed version: symfony 5.4.53, 6.4.41, 7.4.13, 8.0.13. Check the vendor advisory for mitigations.

References

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