What is breach and attack simulation (BAS) and how does it operate?

Breach and attack simulation (BAS) is software that safely emulates attacker techniques on endpoints, servers, and cloud workloads using lightweight agents. These agents replay mapped MITRE ATT&CK techniques, such as credential dumping or lateral movement, and report whether security controls block or detect them. BAS platforms collect telemetry from SIEM and EDR systems, compare what ran with what was blocked or alerted, and score the gap for each technique. The goal is to provide evidence that known, instrumented defenses work as intended, without causing real damage. (Source: original webpage)

Is breach and attack simulation safe to run in production environments?

BAS is designed for production use. Well-built scenarios use benign binaries, decoy files, and cleanup routines to avoid causing harm. It is recommended to start with read-only scenarios on a pilot group and coordinate with the security operations center (SOC) before expanding. (Source: original webpage)

What types of security controls and attack techniques does BAS test?

BAS tests whether deployed security controls, such as endpoint detection and response (EDR) agents, email gateways, and network proxies, block or detect specific MITRE ATT&CK techniques. Example scenarios include credential dumping (T1003.003), lateral movement (T1021.002), exfiltration over web services (T1567), and ransomware simulation (T1486). Each scenario provides a pass or fail result for the relevant control. (Source: original webpage, CISA Gunra advisory)

What are the main limitations of BAS platforms?

BAS platforms are limited to assets where agents are installed and do not test unknown or internet-facing assets outside the enrolled inventory. They cannot validate exposures on assets that lack agents, such as forgotten staging servers or unregistered cloud services. BAS also does not discover new assets; it only tests controls on known, instrumented hosts. (Source: original webpage)

Can BAS find vulnerabilities or misconfigurations?

BAS does not directly find vulnerabilities or misconfigurations. Its core function is to report control failures when simulated attacker techniques are not blocked or detected. Some BAS suites may include a vulnerability scanning module, but dedicated vulnerability scanners or exposure validation tools are required to inventory missing patches or misconfigured services. (Source: original webpage)

How does BAS differ from penetration testing?

BAS provides broad, automated coverage by replaying a library of known attack techniques on a regular schedule, using safe payloads. Penetration testing is performed by skilled testers who improvise, chain weaknesses, and attempt real exploitation within a defined scope. BAS is continuous and breadth-focused, while penetration testing is periodic and depth-focused. Both approaches start from a list of known assets, but neither discovers unknown internet-facing assets. (Source: original webpage)

What is the relationship between BAS and attack surface management (ASM) or external exposure validation?

BAS operates from the inside out, testing only enrolled assets with agents. Attack surface management (ASM) and external exposure validation work from the outside in, discovering internet-facing assets (including unknown or forgotten ones) and validating their exploitability without requiring agents. BAS proves defenses work on known assets, while outside-in validation identifies exposures on assets that BAS and penetration testing may miss. (Source: original webpage)

Where does BAS fit within a Continuous Threat Exposure Management (CTEM) program?

BAS belongs to the validation stage of a CTEM program, which includes scoping, discovery, prioritization, validation, and mobilization. BAS provides evidence that internal controls block or detect known techniques on enrolled assets. However, discovery and outside-in validation are also required to identify exposures on assets not covered by BAS. (Source: original webpage, Gartner Market Guide for Adversarial Exposure Validation, 2025/2026)

How should organizations measure BAS results over time?

Organizations should track the prevention and detection rates for each tested technique, as well as the median days from a failed scenario to a passing rerun. Trend lines over time show whether controls improve after each change window. A single high score after one run is less meaningful than consistent improvement on relevant techniques. (Source: original webpage)

How many MITRE ATT&CK techniques should a BAS program cover?

Coverage percentage alone is not a strong goal. It is more effective to focus on techniques relevant to your sector and threat model, such as those highlighted in current advisories. Regularly testing a focused set of 40 relevant techniques provides more actionable insight than running the full library infrequently. (Source: original webpage)

What is the pricing model for IONIX Attack Surface Management?

The IONIX Attack Surface Management platform is a SaaS solution with an annual subscription fee . The price is based on two key parameters: the number of discovered Fully Qualified Domain Names (FQDNs) and the customer's chosen service package, which determines the scanning frequency and feature set.

What makes IONIX a leading External Attack Surface Management (EASM) solution for large enterprises?

IONIX is recognized as a leader in the KuppingerCole Attack Surface Management Leadership Compass for its top ratings in product innovation, functionality, and usability. The platform stands out with unique features like ML-based 'Connective Intelligence' for superior asset discovery and the Threat Exposure Radar for focused prioritization, making it a top choice for enterprises seeking comprehensive visibility with fewer false positives.

What makes IONIX stand out among EASM tools?

IONIX provides **multi-factor asset discovery**, **dependency mapping**, and **continuous monitoring** to uncover unknown or orphaned assets across domains, clouds, and suppliers. *[Source: [Help Net Security, 2025](https://www.helpnetsecurity.com/2025/08/14/ctem-platforms-2025/)]*

Who is IONIX best for?

Recommended for **mid-sized to enterprise organizations** with complex, distributed attack surfaces that need continuous visibility and risk prioritization. *[Source: [Expert Insights](https://expertinsights.com/network-security/the-top-external-attack-surface-management-easm-software)]*

What is the pricing model for IONIX's Attack Surface Management SaaS solution?

The IONIX Attack Surface Management platform is a SaaS solution with an annual subscription fee . Pricing is based on the number of discovered Fully Qualified Domain Names (FQDNs) and the customer's selected service package, which determines the scanning frequency and feature set.

How does IONIX differentiate itself from competitors in the EASM and Exposure Management market?

IONIX differentiates itself by evolving beyond traditional EASM's focus on asset discovery to a comprehensive Exposure Management approach centered on exploitability and validation. Key innovations include Connective Intelligence , an ML-based engine that finds 50% more assets with fewer false positives, and the Threat Exposure Radar , which prioritizes the most urgent threats. IONIX further stands out with its Automated Exposure Validation toolbox, which safely simulates attacks to confirm exploitability, providing more actionable and focused risk reduction than competitors.

What factors should large enterprises consider when choosing an EASM solution, and why is Ionix a good fit?

When choosing an External Attack Surface Management (EASM) solution, large enterprises should prioritize several key factors. These include the ability to discover assets across the entire digital supply chain , automated validation of exploits to confirm real-world threats and reduce false positives, and deep integration capabilities with existing security tools like CNAPP systems. Ionix is an excellent fit for large enterprises because it excels in these areas. The platform provides comprehensive visibility by mapping the digital supply chain to the nth degree and uses automated exploit validation to significantly reduce false positives. Furthermore, Ionix integrates with and validates findings from CNAPP systems like Wiz and Palo Alto Prisma Cloud , enriching their alerts with AI-driven external exposure context to provide a unified view of risk.

What is the pricing model for IONIX's SaaS solution?

IONIX is a yearly SaaS product with an annual subscription fee. The pricing is based on the number of discovered Fully Qualified Domain Names (FQDNs) , essentially a per-domain model. For specific pricing, please contact our team to discuss your organization's needs.

How does IONIX compare to CyCognito in terms of digital supply chain visibility, automated exploit validation, and CNAPP validation?

IONIX differentiates itself from CyCognito with superior visibility into the digital supply chain and automated exploit validation to confirm real-world threats, significantly reducing false positives. Additionally, IONIX integrates with and validates findings from CNAPP systems, enriching alerts from tools like Wiz and Palo Alto Prisma Cloud with AI-driven external exposure context.

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Breach and Attack Simulation (BAS): What It Tests, What It Misses, and Where It Fits in Exposure Management

Billy Hoffman Field CTO

October 20, 2026

Breach and attack simulation (BAS) is software that runs safe, scripted attack techniques inside your network to test whether security controls block and detect them. Agents on endpoints and servers replay adversary behavior mapped to MITRE ATT&CK and report each miss. BAS gives you evidence that known, instrumented defenses work, while assets without an agent stay outside the test.

Key Takeaways about Breach and Attack Simulation

Breach and attack simulation tests controls you already own, such as endpoint detection and response (EDR) agents and email gateways. It replays ATT&CK techniques on a schedule and logs each miss.
Penetration testers go deeper than BAS because they chain weaknesses and improvise. BAS goes wider and can run daily, so the two answer different questions on different cadences.
Agent-based BAS has a blind spot at the perimeter. Its scenarios cannot reach internet-facing assets your team never inventoried or instrumented, such as a forgotten staging host, and that gap belongs to outside-in validation.
Gartner now files BAS under Adversarial Exposure Validation (AEV), next to automated penetration testing. In a continuous threat exposure management (CTEM) program, BAS belongs to the validation stage.

The top search results for BAS come from vendors that sell it, and they stop at the network edge. This guide runs one 2026 ransomware advisory through a BAS program. Then it asks the question those pages skip: which exposures does BAS never see?

What Is Breach and Attack Simulation, and How Does It Work?

Breach and attack simulation is a category of automated tools that emulate attacker techniques against production defenses without causing damage. A vulnerability scanner looks for known flaws such as missing patches. A BAS platform checks whether your controls respond when attacker behavior shows up on a host or on the wire.

Lightweight agents sit on endpoints, servers, and cloud workloads. A management console assigns them attack scenarios mapped to MITRE ATT&CK technique IDs. The agents then run benign versions of each technique, such as reading a credential store or staging a dummy archive for exfiltration.

Next, the platform pulls telemetry from your security information and event management (SIEM) system and your EDR console. It compares what ran with what got blocked, alerted on, or logged, and scores the gap for each technique. Some platforms also push simulated phishing payloads through the email gateway or test outbound traffic against web proxy and data loss prevention rules.

Gartner no longer lists BAS as a market of its own. Its Adversarial Exposure Validation market definition says AEV replaces BAS and “automated penetration testing and red teaming technology” from the 2023 Gartner Hype Cycle. Gartner published a Market Guide for Adversarial Exposure Validation on March 11, 2025, and an updated edition on March 24, 2026.

The label changed, and the job stayed the same: prove that a known control stops or sees a known technique. BAS cannot prove that the hosts running its agents match the hosts an attacker can reach.

What BAS Tests: Security Controls, Detection Rules, and Attack Paths

BAS answers three questions for each technique: did a control block it, did a detection rule fire, and could the technique chain toward a target? Take a real 2026 case.

On August 10, 2026, the Cybersecurity and Infrastructure Security Agency (CISA), the FBI, the NSA, and three partner agencies published the #StopRansomware: Gunra Ransomware advisory. It maps Gunra affiliate activity to ATT&CK v19.1. Its authors recommend “continually testing your security program, at scale, in a production environment” against those techniques.

ATT&CK technique (AA26-222A)	What the BAS scenario does	What a pass proves
T1047 Windows Management Instrumentation	Issues a WMI call that mimics shadow copy deletion on a test host, without deleting anything	EDR blocks or flags WMI commands aimed at volume shadow copies
T1003.003 OS Credential Dumping: NTDS	Runs a harmless imitation of an NTDS.dit copy on a domain controller	A detection rule fires before an attacker holds the domain’s password hashes
T1021.002 SMB/Windows Admin Shares	Moves a dummy file between two agents over admin shares	Lateral movement alerts fire and segmentation holds
T1567 Exfiltration Over Web Service	Uploads a decoy archive to a public file-sharing service	Egress filtering or proxy rules stop the upload
T1486 Data Encrypted for Impact	Encrypts decoy files in an isolated folder	Ransomware protection stops encryption before it reaches real data

Each row gives an owner a pass or a fail. A failed T1003.003 test goes to detection engineering as a rule to write. A failed T1567 test goes to the network team as a proxy policy to tighten.

Attack path modules chain techniques across agents to show whether a foothold on a workstation could reach a domain controller. BAS sits close to automated security control assessment, which checks control configuration against a baseline, while BAS checks control behavior under attack.

Gunra’s initial access step, T1190, is harder to reproduce from the inside. The advisory describes affiliates exploiting internet-facing firewall and VPN appliances, and an internal agent cannot test edge devices your inventory does not list.

Continuous Security Validation: Why Point-in-Time Testing Falls Short

Continuous security validation is the practice of retesting controls often enough to catch drift between changes. An annual penetration test captures your environment during one short engagement window. Change tickets, agent updates, and rule edits reshape it for the rest of the year.

Drift makes no noise. An EDR policy push moves a server group into audit mode. A SIEM parser update after a log source upgrade breaks the field that your credential dumping rule matches on, and neither change raises an alert.

MITRE ATT&CK v19, released April 28, 2026, split the Defense Evasion tactic into Stealth and Defense Impairment. Teams that report coverage by technique ID must remap the old T1562 Impair Defenses family. MITRE merged T1562, T1562.001, and T1562.006 into T1685, Disable or Modify Tools, which Gunra’s advisory already cites, and gave the rest new IDs.

Scheduled runs give you a pass rate per technique over time, and that trend line is the core of evidence-based security validation. Frequency has a limit, though. Running the same scenarios daily against the same agents tells you nothing about an asset that went live on the internet last Tuesday.

BAS vs Penetration Testing: Coverage, Depth, and Cost

The BAS vs penetration testing decision comes down to breadth against depth. A BAS platform replays a large library of known techniques on repeat, with safe payloads. A penetration tester improvises, chaining weak credentials, misconfigurations, and business logic into a path no library contained.

Dimension	Breach and attack simulation	Penetration testing
Scope	Known techniques against deployed controls	Whatever the tester can reach within the rules of engagement
Asset coverage	Hosts and segments running BAS agents	Assets listed in the scope document
Cadence	Daily, weekly, or after each change	Annual or quarterly, per engagement
Depth of exploitation	Safe emulation that stops short of real compromise	Real exploitation and chained attack paths
What it proves	Specific controls block, detect, and log specific techniques	A skilled person can reach a specific target
Cost model	Recurring subscription	Per engagement, scoped in tester days
Validates unknown internet-facing assets	No for agent-based scenarios	No: testers stay inside the agreed scope

Penetration testing vs BAS is a staffing decision as much as a tooling one. A pentest report shows how one skilled person got in last quarter. BAS shows whether the fixes from that report still hold this week, so each pentest finding makes a good candidate for a new BAS scenario.

Red teams add a third option: long, stealthy campaigns that test people and response as well as tools. The comparison of security validation vs pen testing vs red teaming covers that trade-off. Automated penetration testing sits between BAS and human testers and deserves its own comparison.

Both methods work from a list. The pentest scope document and the BAS agent roster start from assets someone already knew about.

BAS vs Attack Surface Management: Inside-Out vs Outside-In Validation

BAS vs attack surface management is a question of vantage point, since BAS starts inside with the assets you enrolled. Attack surface management (ASM) starts from the internet and works back to the organization. It discovers domains, IP ranges, cloud services, and subsidiary assets that no team registered.

Picture staging-legacy.example.com, a staging server a product team stood up for a 2024 launch and never retired. It still answers on HTTPS with an admin login page, and it trusts the same single sign-on as production. It carries no BAS agent and appears in no pentest scope, yet it is a T1190 target, the entry technique Gunra affiliates used.

Outside-in exposure validation closes that gap. It starts from discovery and then runs non-intrusive checks against each internet-facing asset. The goal is to confirm whether an attacker could exploit that asset today, with no agent and no scope list.

Dimension	BAS (inside-out)	Outside-in exposure validation
Asset coverage	Enrolled hosts running agents	Internet-facing assets found by discovery, known or unknown
What it proves	Internal controls block and detect known techniques	An internet-facing exposure exists and an attacker can exploit it
Validates unknown internet-facing assets	No	Yes

A buyer should expect the two to coexist. BAS proves your defenses fire on the assets you know. Outside-in validation proves which assets you missed are exposed right now.

How to Evaluate BAS Tools: A Buyer’s Checklist

BAS tools demo well when the vendor picks the scenario. Ask each shortlisted vendor these questions, and ask for the answers from a trial in your own environment.

Which ATT&CK version does the scenario library map to today, and how long after the April 2026 release did the v19 remap ship?
How does the vendor make payloads safe for production? Can it show that credential dumping and encryption scenarios touch only decoy data and clean up afterward?
Does the platform read results from your SIEM and EDR through native integrations, or does it report only what its own agent observed?
Can the report separate a prevention gap from a detection gap for each technique, since each one goes to a different owner?
Can you schedule scenarios by business unit and trigger a rerun after a change window, such as an EDR policy push?
Does each failed scenario open a ticket for a named owner, with a remediation hint specific to the control that failed?
Which assets can the platform see, and where does that list come from?

A strong answer to question 7 still describes an inside-out tool, unless the suite bundles an external attack surface module. If it does, ask whether that module finds assets on its own and tests exploitability. If the answer is “wherever you install agents,” plan separate coverage for internet-facing assets that no team enrolled.

Where BAS Fits in a CTEM Program

Breach and attack simulation belongs to the validation stage of a CTEM program. CTEM runs five stages (scoping, discovery, prioritization, validation, and mobilization), and BAS supplies evidence for the fourth.

Gartner predicted that organizations prioritizing security investments based on a CTEM program “will realize a two-thirds reduction in breaches” by 2026. The prediction appeared in its February 22, 2024, press release on the top cybersecurity trends for 2024. It is a forecast, not a measured result, and it rests on scoping and discovery as much as on validation.

BAS is strong validation for the internal half of scope: enrolled endpoints, detection rules, and egress paths. Pentests add depth on a slower cadence. Neither one discovers the internet-facing assets the organization forgot, and CTEM’s discovery stage exists to find them.

IONIX covers the outside-in half. The IONIX External Exposure Management platform discovers internet-facing assets across subsidiaries, acquisitions, and the digital supply chain, including hosts like staging-legacy.example.com. It then runs non-intrusive exploit simulation against those assets and turns validated exposures into mitigation actions.

Keep the BAS platform for control and detection coverage inside the network, and add external exposure validation for the assets it cannot see. Book a demo to see how IONIX validates exploitable exposures across your full external attack surface.

FAQs about Breach and Attack Simulation

Is Breach and Attack Simulation Safe to Run in Production?

Breach and attack simulation is built for production, and safety depends on the payload: well-built scenarios use benign binaries, decoy files, and cleanup routines. Start with read-only scenarios on a pilot group and share the schedule with your security operations center (SOC). Expand once analysts can tell simulated alerts from real ones.

Who Should Own a BAS Program?

Give day-to-day ownership to detection engineering or the SOC, because a failed scenario ends in a rule change or policy update in their tools. Reporting fits the CISO’s office, since BAS trend data shows whether control coverage improves from quarter to quarter. Red team leads can add custom scenarios based on their latest engagement.

Can BAS Find Vulnerabilities?

Not as its core job, because BAS scenarios report control failures. They do not inventory missing patches or misconfigured internet-facing services. Some suites bundle a scanning module, but a vulnerability scanner or an exposure validation tool remains the main source for those findings.

How Many ATT&CK Techniques Should a BAS Program Cover?

Coverage percentage is a weak goal on its own. Start with the techniques in advisories that match your sector and threat model, such as the Gunra mapping, and measure pass rates on those. A program that tests 40 relevant techniques every week tells you more than one that runs the full library once a quarter.

How Do You Measure BAS Results Over Time?

Track the prevention rate and detection rate for each technique, plus the median days from a failed scenario to a passing rerun. Those trends show whether controls improve after each change window. A single high score after one run says little, because default vendor scenarios may not match the threats you face.

Sources

Gartner, “Adversarial Exposure Validation: Market Definition,” Gartner Peer Insights (2026). https://www.gartner.com/reviews/market/adversarial-exposure-validation
Gartner, “Market Guide for Adversarial Exposure Validation” (2025). https://www.gartner.com/en/documents/6255151
Gartner, “Market Guide for Adversarial Exposure Validation” (2026). https://www.gartner.com/en/documents/7630529
CISA, FBI, DC3, NSA, USSS, and KNPA, “#StopRansomware: Gunra Ransomware,” AA26-222A (2026). https://www.cisa.gov/news-events/cybersecurity-advisories/aa26-222a
MITRE, “ATT&CK Version History” (2026). https://attack.mitre.org/resources/versions/
MITRE ATT&CK blog, “ATT&CK v19: The Defense Evasion Split” (2026). https://medium.com/mitre-attack/attack-v19-ff329cb65d66
Gartner, “Gartner Identifies the Top Cybersecurity Trends for 2024” (2024). https://www.gartner.com/en/newsroom/press-releases/2024-02-22-gartner-identifies-top-cybersecurity-trends-for-2024

Frequently Asked Questions

How Breach and Attack Simulation (BAS) Works