CVE-2026-45075 symfony CVE debrief

Who should care

Developers and administrators using Symfony versions prior to 7.4.12 or 8.0.12 should apply patches to prevent potential security bypass attacks. Security teams and vulnerability management teams should review the CVE record and NVD entry to understand the vulnerability and affected versions. Operators and platform administrators should verify configurations and apply patches where applicable.

Technical summary

Symfony, a PHP framework for web and console applications, had method-scoped #[IsGranted], #[IsSignatureValid], and #[IsCsrfTokenValid] attributes that could be configured for GET requests only. However, Symfony routes HEAD requests to the GET handler, skipping attribute checks. This allowed protected controllers to execute, potentially leaking headers or causing side effects. The issue is fixed in Symfony versions 7.4.12 and 8.0.12. Affected deployments should be reviewed for exposure, and patches should be applied to prevent potential security bypass attacks.

Defensive priority

High priority should be given to applying patches for Symfony versions prior to 7.4.12 or 8.0.12 to prevent potential security bypass attacks.

Recommended defensive actions

• Apply patches to upgrade Symfony to version 7.4.12 or 8.0.12
• Review and update affected applications to ensure proper attribute configuration
• Monitor for potential security bypass attempts
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD entry provide details on the vulnerability and affected versions. Patches are available in Symfony versions 7.4.12 and 8.0.12. Evidence limits suggest that the vulnerability is exploitable in certain configurations, but full scope and impact remain under review. Defenders should verify configurations, review vendor advisories, and apply patches where applicable. Additional information from vendor sources and security researchers may be necessary to fully understand the vulnerability.

Official resources