ShutterGap is a reported visibility gap in AWS monitoring where a resource can be created, exposed, and removed between security scans. It is not a vulnerability in AWS itself; it is a timing problem in how posture tools collect and evaluate cloud state.
This matters because cloud defenses often rely on periodic sampling through tools such as CSPM, CNAPP, AWS Config, and Security Hub. If inventory updates lag behind the control plane, a short-lived public bucket, security group change, or other risky setting may leave no finding behind. In attacks, that can help an operator hide transient exposure. In defense, the answer is tighter guardrails: continuous recording for critical assets, event-driven alerts on creation and policy changes, and preventive controls such as restrictive defaults and Block Public Access where applicable.