CISA Ties Decoy Systems to Zero Trust

CISA has published new guidance for critical infrastructure organizations on deploying decoy systems, positioning them as a complement to Zero Trust models that assume an adversary has already gained some level of access. The document walks defenders through what decoys are, how to place them, and how to run a decoy program as an operational process rather than a one-off deployment.

Decoys Assume Breach Already Happened

Zero Trust, as CISA describes it, continuously verifies all access. Cyber decoys fit into that model by starting from the premise that an intrusion has already occurred somewhere in the environment, and by giving defenders something to watch when it does.

According to CISA, cyber decoys are assets that look like legitimate systems, accounts, or data but are built to distract adversaries, detect their presence, or help collect cyber threat intelligence (CTI). The agency frames them as a way to identify, observe, and block malicious activity early, gather and analyze CTI, and allocate resources more effectively.

CISA's guidance states: "Decoy techniques are incremental, cost-effective, and scalable, allowing organizations to introduce them without major architectural changes." That framing places decoys alongside existing defenses rather than requiring a rebuild of the network to support them.

Where Decoys Belong in a Network

Placement matters more than volume. CISA advises organizations to put decoys where users rarely or never interact with them, and to configure those assets so they generate high-fidelity alerts. The logic is straightforward: a legitimate user has little reason to touch a system nobody uses, so any interaction with it is worth examining.

The guidance also describes what decoys should be built to do once an adversary finds them. They should divert attackers toward decoy data, create a misleading picture of the environment during reconnaissance, and lure threat actors into downloading large amounts of non-sensitive or meaningless data.

Beyond distraction, CISA says decoys should steer adversaries into controlled environments where their operations — designed to resemble real-world activity — can be observed and where CTI can be collected more efficiently.

The Tooling Behind a Decoy Program

CISA groups the systems used in deception under a handful of categories, and the guidance details the benefits of each type along with how they should be deployed. The document also provides example scenarios to illustrate decoy techniques in practice.

• Lures
• Tripwires
• Decoy artifacts
• Honeytokens
• Honeypots

Effective deployment of these systems, the agency says, is a three-phase operational process covering preparation, execution, and understanding. Treating deception as a cycle rather than a product install is central to how CISA presents the material.

Preparation: Goals Before Deployment

The first phase is the one organizations most often skip. During preparation, CISA says, organizations must evaluate their threat landscape, set clear operational goals, and map out the perceptions and reactions they want to provoke in an adversary.

That phase also includes establishing deployment channels and defining success metrics — the measures that will later determine whether the decoys are doing what they were meant to do. Without those definitions set in advance, the data a decoy generates is difficult to interpret.

The emphasis on mapping desired adversary behavior is notable: it treats deception as an exercise in predicting how an intruder will respond to what they find, not simply in scattering fake systems across a network.

Turning Alerts Into Intelligence

Once decoys are live, the work shifts to execution and then to analysis. CISA says organizations need to turn the data they collect into actionable intelligence, feed that intelligence back into defensive efforts, and review both successes and failures as part of continued improvement.

This is where the CTI component of the guidance connects to day-to-day operations. A decoy that only trips an alarm has served one purpose; a decoy program that produces intelligence about adversary tools and behavior serves another, and the guidance treats the second as part of the design.

Built for Defensive Teams at All Levels

"CISA developed this guidance to help defensive teams at varying levels of cybersecurity maturity plan and implement cyber decoy strategies that strengthen their detection and response capabilities. Many organizations struggle to detect adversaries who use legitimate credentials, native tools, and living off the land (LOTL) techniques to conduct discovery, move laterally, and access data."

— CISA

That statement identifies the problem the guidance is written around: adversaries who do not rely on malware or exploits that signature-based tools would catch, but instead use credentials and tools already present in the environment. Living off the land techniques, as described by CISA, cover discovery, lateral movement, and access to data — activity that can look ordinary from the outside.

Decoys and Threat Intelligence Collection

The intelligence-gathering role of decoys runs through much of the guidance. CISA notes that decoys facilitate collection of cyber threat intelligence, and describes controlled environments as places where adversary operations can be observed more efficiently than in the noise of a production network.

That makes the guidance relevant to teams that already run detection engineering or threat intelligence functions, since the output of a decoy program is intended to feed those efforts rather than sit in a separate console.

The agency also emphasizes that deception should not be a standalone project. In CISA's framing, decoys complement Zero Trust by covering the scenario Zero Trust itself is designed around — an adversary who has already obtained some level of access.

Reading the Guidance

The document is published as a PDF on CISA's site. It sets out the benefits of each decoy type, how decoys should be deployed, and example scenarios for applying the techniques.

CISA's guidance is aimed at critical infrastructure organizations, a sector where the consequences of an undetected intrusion extend beyond a single company. The agency describes decoys as incremental and scalable, meaning organizations can start with a limited deployment and expand it over time.

The guidance sits alongside other CISA work on detection and response, and its central argument is that watching for activity on systems nobody should be using is a practical way to catch adversaries who have otherwise blended into normal operations.

Why It Matters

For critical infrastructure operators, the guidance reflects a shift in emphasis that has been building across the security industry: detection may depend less on keeping every adversary out and more on noticing when one is already inside. CISA's description of adversaries using legitimate credentials and native tools suggests that many intrusions will not produce obvious technical artifacts, which could make decoys one of the few reliable sources of high-fidelity signals in that scenario.

The operational burden is real. A decoy program requires preparation, defined success metrics, and a process for turning collected data into intelligence — work that many teams may not have staffed. But because CISA describes the techniques as incremental and cost-effective, organizations could adopt them gradually rather than treating deception as an all-or-nothing investment.

The broader implication for the industry is that deception is being treated less as an exotic add-on and more as a component of a mature defensive posture, one that pairs with Zero Trust rather than replacing it. For defenders weighing where to spend limited resources, the guidance offers a documented starting point: pick systems users should never touch, watch them closely, and build from there.