What is Breach & Attack Simulation (BAS)?
Breach & Attack Simulation (BAS) is a category of security testing tools that automatically and continuously replay attacker techniques against an organization's live environment to verify whether security controls detect and block them. BAS tools map tests to frameworks such as MITRE ATT&CK so teams can see exactly which techniques succeed or fail.
What it does
BAS tools run scheduled or on-demand attack scenarios against production or staging environments without requiring manual red-team effort each time. A typical platform will:
- Execute attack chains that mimic real adversary behavior, from initial access through lateral movement to data exfiltration
- Map every test to MITRE ATT&CK tactics and techniques
- Record whether each simulated attack was blocked, alerted on, or missed entirely
- Produce a gap report showing which controls failed and which detection rules need tuning
- Rerun the same scenarios after a fix to confirm the gap is closed
Some platforms run as lightweight agents installed on endpoints. Others are agentless and test from the network perimeter or cloud control plane. Certain tools also include cyber range environments for hands-on training and incident-response drills alongside automated simulation.
Why teams buy it
Security controls drift. A firewall rule changes, an EDR policy is misconfigured, or a new cloud workload is deployed outside the standard baseline. BAS gives security teams a continuous, evidence-based answer to the question: "Are our controls actually working right now?"
Teams also use BAS to satisfy audit requirements, prioritize remediation backlogs, and justify security spending with concrete pass/fail data rather than assumptions.
What to look for
- ATT&CK coverage: How many techniques does the platform simulate, and how often is the library updated with new adversary behaviors?
- Deployment model: Agent-based, agentless, or both. Agentless suits cloud and OT environments where installing software is restricted.
- Integration with detection tools: Can the platform pull alert data from your SIEM or EDR automatically to score each test without manual review?