The term kill chain was originally used as a military concept related to the structure of an attack; consisting of
force dispatch to target,
decision and order to attack the target, and
finally the destruction of the target.
Conversely, the idea of "breaking" an opponent's kill chain is a method of defense or preemptive action.
More recently, Lockheed Martin adapted this concept to information security, using it as a method for modeling intrusions on a computer network.
Developed by Lockheed Martin, the Cyber Kill Chain framework is part of the Intelligence Driven Defense model for identification and prevention of cyber intrusions activity.
The model identifies what the adversaries must complete in order to achieve their objective.
The seven steps of the Cyber Kill Chain enhance visibility into an attack and enrich an analyst’s understanding of an adversary’s tactics, techniques and procedures.
The attacker gathers information on the target before the actual attack starts.
Many security professionals feel that there is nothing that can be done about this stage, but that’s beyond wrong.
Quite often, cyber attackers collect information on their intended targets by searching internet sites like LinkedIn or Instagram.
They may also try to gather intel through techniques such as calling employees, email interactions, or dumpster diving.
This is where secure behaviors can have a big impact.
An aware workforce will know they are a target and limit what they publicly share.
They will authenticate people on the phone before they share any sensitive information.
They safely dispose of and shred sensitive documents.
Does this totally neutralize this stage?
Absolutely not, but then again, no control fully does.
However, this can put a big dent in the attacker’s capabilities to gather information.
A properly trained workforce can report suspicious activity, such as odd phone calls probing for more information.
The cyber attacker does not interact with the intended victim.
Instead, they create their attack.
For example, the attacker may create an infected Microsoft Office document paired with a customized phishing email, or perhaps they create a new strain of self-replicating malware to be distributed via USB drive.
There are few security controls, including security awareness, that may impact or neutralize this stage, unless the cyber attacker does some limited testing on the intended target.
Transmission of the attack to the intended victim(s).
For example, this would be sending the actual phishing email or distributing the infected USB drives at a local coffee shop or cafe.
While there is an entire technical industry dedicated to stopping this stage, people also play a critical role.
While people aren’t proficient at remembering lots of new information, they are very good at being adaptable.
They generally follow that “this does just not seem right” instinct.
In addition, the 2019 Verizon DBIR found passwords and phishing as the two primary attack vectors, both involving people.
As such, it is people and not technology that are the first line of defense in detecting and stopping many of these attacks, to include new or custom attacks such as CEO Fraud or Spear Phishing.
In addition, people can identify and stop attacks that most technologies cannot even filter, such as attacks over the phone.
A trained workforce greatly reduces this attack surface area.
This implies actual ‘detonation’ of the attack, such as the exploit running on the system.
Trained people ensure the systems they are running are updated and current.
They ensure they have anti-virus running and enabled.
They ensure that any sensitive data they are working with is on secured systems, making them far more secure against exploitation.
The attacker installs malware on the victim.
Not all attacks require malware, such as a CEO fraud attack or harvesting login credentials.
However, just like exploitation when malware is involved, a trained and secure workforce can help ensure they are using secure devices that are updated, current, and have anti-virus enabled, which would stop many malware installation attempts.
In addition, this is where we begin to go beyond just the “human firewall” and leverage the “human sensor”.
A key step in detecting an infected system is to look for abnormal behavior.
Who better to detect abnormal behavior than the people using the system every day?
This implies that once a system is compromised and/or infected, the system has to call home to a Command and Control (C&C) system for the cyber attacker to gain control.
This is why ‘hunting’ has become so popular.
They’re looking for abnormal outbound activities like this.
Once the cyber attacker establishes access to the organization, they can then execute actions to achieve their objectives.
Motivations vary greatly depending on the threat actor.
It may include political, financial, or military gain, so it is very difficult to define what those actions will be.
Once again, this is where a trained workforce of human sensors embedded throughout your organization can vastly improve
your ability to detect and respond to an incident, and
your resilience capabilities.
In addition, secure behaviors will make it far more difficult for a successful adversary to pivot throughout the organization and achieve their objectives.
Behaviors such as the use of strong, unique passwords, authenticating people before sharing sensitive data, or reviewing their last login are some of the many behaviors that make the attacker’s life far more difficult and result in them being far more likely to be detected.
Different security techniques bring forward different approaches to the cyber kill chain – everyone defines the stages slightly differently.
Alternative models of the cyber kill chain combine several of the above steps into a C&C stage (command and control, or C2) and others into an ‘Actions on Objective’ stage.
Some combine lateral movement and privilege escalation into an exploration stage; others combine intrusion and exploitation into a ‘point of entry’ stage.
It’s a model often criticized for focusing on perimeter security and limited to malware prevention.
When combined with advanced analytics and predictive modeling, however, the cyber kill chain becomes critical to data security.
With the above breakdown, the kill chain is structured to reveal the active state of a data breach. Each stage of the kill chain requires specific instrumentation to detect cyber attacks.