CVE-2026-6270
@fastify/middie versions 9.3.1 and earlier do not register inherited middleware directly on child plugin engine instances. When a Fastify application registers authentication middleware in a parent scope and then registers child plugins with @fastify/middie, the child scope does not inherit the parent middleware. This allows unauthenticated requests to reach routes defined in child plugin scopes, bypassing authentication and authorization checks. Upgrade to @fastify/middie 9.3.2 to fix this issue. There are no workarounds.
Attack Parameters
Technical Impact
Time Line
Key Metrics
Recommended Solution
Immediate Action Plan
1. Inventory
Identify all affected systems in your infrastructure.
2. Assessment
Assess exposure and criticality for your organization.
3. Mitigation
Apply patches or available workarounds.
4. Verification
Test and confirm effectiveness of applied measures.
⚠️ MAXIMUM PRIORITY - Immediate action required