CVE-2026-48505 Overview
CVE-2026-48505 is a race condition vulnerability in Filament, a collection of full-stack components for accelerated Laravel development. The flaw affects versions from 4.0.0 through 4.11.4 and 5.0.0 through 5.6.4. It allows the same multi-factor authentication (MFA) recovery code to be reused through concurrent submission, breaking the single-use guarantee.
Critical Impact
An attacker possessing a victim's password and recovery codes can establish multiple authenticated sessions per recovery code by submitting requests in parallel, materially extending unauthorized access compared to the expected single-use enforcement.
Affected Products
- Filament versions 4.0.0 to 4.11.4
- Filament versions 5.0.0 to 5.6.4
- Laravel applications using app-based MFA with recovery codes enabled
Discovery Timeline
- 2026-06-22 - CVE CVE-2026-48505 published to NVD
- 2026-06-23 - Last updated in NVD database
Technical Details for CVE-2026-48505
Vulnerability Analysis
The vulnerability is a race condition [CWE-362] in Filament's recovery code redemption logic for app-based MFA. Recovery codes are intended to be single-use credentials that authenticate a user when their primary MFA factor is unavailable. The code validation and invalidation steps are not executed atomically.
An attacker submitting multiple authentication requests with the same recovery code in parallel can pass validation in each concurrent request before any of them marks the code as consumed. Each successful submission produces an authenticated session. Batching parallel submissions wider increases the number of valid sessions obtained per recovery code burned.
The issue does not affect email-based MFA. It only applies when recovery codes are enabled on the affected Filament versions. Exploitation requires the attacker to already possess both the user's password and valid recovery codes, which raises the attack complexity.
Root Cause
The root cause is the absence of an atomic check-and-invalidate operation when verifying recovery codes. Filament reads the stored recovery code, validates it, and then marks it as used in separate, non-transactional steps. Concurrent requests interleave between the check and the update, allowing multiple validations against the same code state.
Attack Vector
The attack vector is network-based and requires no user interaction at exploitation time. An attacker scripts simultaneous HTTP POST requests to the MFA recovery endpoint using the same recovery code. The server processes each request through the vulnerable validation path before any has committed the code's invalidation, yielding multiple session tokens.
The vulnerability mechanism is described in the GitHub Security Advisory GHSA-mc5j-f6wx-h9qh.
Detection Methods for CVE-2026-48505
Indicators of Compromise
- Multiple successful MFA recovery authentication events for the same user account within a sub-second window.
- Concurrent session creation from the same or differing source IPs immediately following a recovery code submission.
- Authentication logs showing the same recovery code identifier accepted in more than one session record.
Detection Strategies
- Correlate Filament authentication logs to identify multiple session establishments tied to a single recovery code submission burst.
- Alert on parallel HTTP requests to MFA recovery endpoints originating from automation tooling or scripted clients.
- Baseline normal recovery code usage frequency per user and flag deviations.
Monitoring Recommendations
- Forward Laravel and Filament authentication logs to a centralized logging platform for correlation and retention.
- Monitor for new authenticated sessions that appear within milliseconds of one another for the same user identity.
- Track recovery code consumption events and alert when a single code maps to multiple successful authentications.
How to Mitigate CVE-2026-48505
Immediate Actions Required
- Upgrade Filament to version 4.11.5 or 5.6.5, which contain the fix.
- Audit authentication logs for prior recovery code reuse patterns and invalidate suspicious sessions.
- Force regeneration of recovery codes for all users following the upgrade.
Patch Information
Filament released patched versions 4.11.5 and 5.6.5 that enforce atomic validation and invalidation of recovery codes. Administrators should update via Composer and verify the installed version. Patch details are documented in the Filament Security Advisory.
Workarounds
- Disable recovery codes for app-based MFA until the upgrade is applied.
- Require users to re-enroll in MFA and regenerate recovery codes after patching.
- Enforce rate limiting on the MFA recovery endpoint to constrain parallel submission attempts.
# Configuration example
composer require filament/filament:^5.6.5
# or for the 4.x branch
composer require filament/filament:^4.11.5
php artisan config:clear
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
