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.
Exploitation Probability (EPSS)
Low PriorityThe Exploit Prediction Scoring System (EPSS) uses machine learning to estimate the probability that a vulnerability will be exploited in the wild within the next 30 days.
7-Day Exploitation Trend
Vulnerability Timeline
2 eventsThreat Actor Attribution
PREMIUM INTELRemediation & Mitigation
SOLUTIONOfficial patches and mitigation steps are available for this vulnerability.
apt-get update && apt-get upgrade -y specific-package
# Verify installation
dpkg -l | grep package-name
Affected Products
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Vulnerability Details
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