Breach and attack simulation (BAS): prove your controls stop what you think they stop.
Breach and attack simulation (BAS) runs safe, repeatable versions of real attacker techniques against your environment and records what each security control did. Not what the vendor says it does. What it did, today, with your configuration. This guide covers how BAS works, what it proves and where it stops.
How Breach and Attack Simulation Works
Four moving parts, run on a schedule. The value comes from repetition: the same technique, rerun after every change, tells you when a control drifts.
Agents or sensors
Lightweight agents on test endpoints and servers, plus cloud, email and network targets, act as the attacker's foothold.
Attack library
Safe implementations of real techniques, mapped to MITRE ATT&CK and updated as new threats appear.
Scenarios
Techniques chained into realistic sequences, such as a ransomware precursor or a known actor's playbook.
Outcome collection
Results pulled from your controls and SIEM so each step gets a verdict, not just an execution log.
Every simulated technique ends in exactly one of these.
A control blocked the technique before it completed.
MEANS · The control works for this technique, today.The technique ran, and an alert reached the SOC within the expected time.
MEANS · Someone would know, in time to respond.Telemetry exists, but no alert fired.
MEANS · Evidence after the fact; nobody is told during the attack.The technique completed with no block, alert or usable log.
MEANS · A blind spot. Fix the control or add a log source.BAS Attack Vectors and the Controls Each One Tests
Each vector targets a different layer of your stack. Coverage across all of them is what turns BAS from a demo into a program.
Malicious attachments, links and spoofed senders delivered to test mailboxes.
T1566 TESTS · Secure email gateway, sandboxing, user reportingEndpoint
Execution, persistence, privilege escalation and credential access on test hosts.
T1059 · T1053 · T1003 TESTS · EDR, application control, hardeningLateral movement
Remote services, admin shares and credential reuse between test hosts.
T1021 · T1550 TESTS · Segmentation, EDR, identity controlsCommand and control
Beaconing over HTTP, DNS and other protocols to test infrastructure.
T1071 · T1572 TESTS · Web proxy, DNS security, NDRExfiltration
Synthetic sensitive files sent over web, cloud storage and alternative protocols.
T1048 · T1567 TESTS · DLP, CASB, egress filteringWeb application
Common web attack payloads against a test application behind your WAF.
T1190 TESTS · WAF, API gatewayCloud
Misuse of cloud APIs and identities in a sandboxed account.
T1078.004 · T1530 TESTS · CSPM, CDR, cloud loggingDetection pipeline
Known-bad telemetry sent end to end to confirm rules fire.
Any technique TESTS · SIEM rules, log pipeline, SOARBreach and Attack Simulation Example: A Ransomware Chain, Technique by Technique
Eight ATT&CK techniques chained the way a ransomware operator would run them, executed with safe payloads on two test hosts. Each step records which control responded and how.
Illustrative run · synthetic hosts and results · 20 s replay
Detection Drift Example: The Rule That Stopped Firing
Credential dumping was detected every week for a year. Then a log pipeline update renamed one field. The EDR still saw it, the SIEM still received it, and the alert never fired again. Only a rerun noticed.
Detection validation →Illustrative finding · synthetic data
BAS vs Penetration Testing vs Exposure Validation
BAS asks whether your controls work. Pentesting asks how far a skilled human can get. Exposure validation asks which of your weaknesses are actually exploitable. Full BAS vs pentest comparison →
Eight Questions to Ask a BAS Vendor
Ask for a proof of value on your own controls. A slide of supported techniques tells you very little.
Security validation buyer's guide →What does it actually execute?
Ask how each technique is implemented and what makes it safe on a real host.
How are outcomes collected?
Verdicts should come from your controls and SIEM, not assumed from execution success.
Can it tell detected from logged?
The difference between an alert and a log line is the difference between response and forensics.
How current is the library?
Ask how quickly new techniques and actor playbooks are added, and who reviews them.
Can scenarios chain techniques?
Single techniques test controls; chains test whether the attack as a whole gets through.
What does it need deployed?
Agents, sensors and test infrastructure all carry operational cost and change risk.
How does it show drift?
Week-over-week changes per technique are the most valuable thing BAS produces.
Who approves each run?
Production simulation needs scope, approval and an audit trail, by design.
Control Validation and Exposure Validation, in One Governed Loop
Hayrok runs BAS-style technique simulations to prove what your controls prevent and detect, and connects the results to the exposures attackers would actually use to reach those controls. Every run is approved, scoped and recorded as evidence.
Technique simulation
Safe implementations of ATT&CK techniques, chained into scenarios from the approved library.
Four-outcome verdicts
Results pulled from your controls and SIEM so each step is prevented, detected, logged or missed.
Drift tracking
Every rerun is compared with the last; regressions open as Drifted findings with the diff.
Tied to real exposure
Control gaps are linked to the validated attack paths that would reach them.
Governed and recorded
Each run is scoped and approved, and stored as evidence in Evidence Fabric.
Breach and Attack Simulation FAQ
Breach and attack simulation (BAS) is automated, continuous testing that runs safe versions of real attacker techniques against your environment and records how each security control responded: prevented, detected, logged or missed.