CVE-2026-48505

Filament: Multi-factor authentication (app) recovery codes can still be used multiple times via concurrent submission

A flaw in the handling of recovery codes for app-based multi-factor authentication allows the same recovery code to be reused via concurrent submission. This issue does not affect email-based MFA. It also only applies when recovery codes are enabled.

If an attacker gains access to both the user's password and their recovery codes, they get two authenticated sessions per recovery code burned instead of one, or more if they batch the parallel submissions wider, materially extending the attacker's window of access compared to what the single-use guarantee implies.

Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing. Typical impact: TOCTOU exploits, data corruption, or privilege escalation.

CVE-2026-48505 has a CVSS score of 7.4 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (4.11.5, 5.6.5); upgrading removes the vulnerable code path.

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1. What is CVE-2026-48505? CVE-2026-48505 is a high-severity race condition vulnerability in filament/filament (composer), affecting versions >= 4.0.0, < 4.11.5. It is fixed in 4.11.5, 5.6.5. Multiple concurrent operations access a shared resource without proper synchronization, producing unpredictable results depending on timing.
2. How severe is CVE-2026-48505? CVE-2026-48505 has a CVSS score of 7.4 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of filament/filament are affected by CVE-2026-48505? filament/filament (composer) versions >= 4.0.0, < 4.11.5 is affected.
4. Is there a fix for CVE-2026-48505? Yes. CVE-2026-48505 is fixed in 4.11.5, 5.6.5. Upgrade to this version or later.
5. Is CVE-2026-48505 exploitable, and should I be worried? Whether CVE-2026-48505 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-48505 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-48505?
   • Upgrade filament/filament to 4.11.5 or later
   • Upgrade filament/filament to 5.6.5 or later

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