CVE-2026-48166 filamentphp CVE debrief

Who should care

Organizations using Filament for Laravel development should be aware of this vulnerability and take necessary actions to protect their applications. Specifically, those using affected versions (4.0.0 through 4.11.4 and 5.6.4 or earlier) should update to a patched version as soon as possible. Security teams and developers responsible for maintaining Laravel applications that utilize Filament should prioritize this vulnerability and ensure that appropriate measures are taken.

Technical summary

CVE-2026-48166 is a medium-severity vulnerability with a CVSS score of 5.3. It is caused by an observable timing discrepancy on the login page of Filament, which allows unauthenticated attackers to determine if an account exists for a given email address. The vulnerability is due to the way the login page handles authentication requests, leading to a potential timing side-channel attack. The CVSS vector for this vulnerability is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N, indicating a network attack vector with low attack complexity and no required privileges or user interaction. The vulnerability's impact is limited to confidentiality, with no impact on integrity or availability.

Defensive priority

This vulnerability should be prioritized as medium severity. While it does not allow for direct exploitation or significant data breaches, it can be used as a reconnaissance tool by attackers to gather information about valid email addresses associated with the application.

Recommended defensive actions

• Update Filament to version 4.11.5 or 5.6.5, or later, to apply the fix.
• Review and update affected applications that use Filament to ensure they are running a patched version.
• Consider implementing additional monitoring and logging to detect potential exploitation attempts.
• Conduct a thorough inventory of systems and applications that use Filament to identify all potentially affected assets.
• Develop a remediation plan for affected systems, prioritizing updates and patches.

Evidence notes

The CVE-2026-48166 vulnerability was publicly disclosed on June 22, 2026, and the CVE record was last modified on June 23, 2026. The vulnerability was reported by an unknown source and is tracked by the CVE.org and NVD databases. The official CVE record and NVD detail pages provide additional information about the vulnerability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.