The concept of a cyber attack kill chain originates from military terminology and is used to describe the sequence of stages that an adversary follows to achieve their objectives in a cyber attack. This model helps cyber security professionals understand and counteract the various phases of a cyber attack. The most widely recognized framework is the Lockheed Martin Cyber Kill Chain, which breaks down an attack into seven distinct phases: Reconnaissance, Weaponization, Delivery, Exploitation, Installation, Command and Control (C2), and Actions on Objectives.

1. Reconnaissance: This is the initial stage where the attacker gathers information about the target. They may research public data, scan networks, and probe systems for vulnerabilities. The goal is to identify weak points that can be exploited later.
2. Weaponization: In this phase, the attacker creates or acquires a malicious payload (e.g., malware, exploit kit) designed to exploit the identified vulnerabilities. This often involves coupling the payload with a delivery mechanism, such as a phishing email or a malicious website.
3. Delivery: The attacker transmits the weaponized payload to the target. Common delivery methods include email attachments, malicious links, or compromised websites. The effectiveness of this phase relies on the method’s ability to reach and entice the target to interact with it.
4. Exploitation: Upon delivery, the malicious payload is triggered, exploiting a vulnerability to gain initial access to the target system. This can involve executing a malicious script, exploiting a software bug, or using social engineering techniques to trick the user into granting access.
5. Installation: After exploitation, the attacker installs a backdoor or other persistent mechanism to maintain access to the compromised system. This step ensures that the attacker can regain access even if the system is rebooted or patched.
6. Command and Control (C2): With persistent access established, the attacker sets up communication channels to remotely control the compromised system. This often involves connecting to a C2 server to receive commands and exfiltrate data. These channels are typically encrypted and designed to evade detection.
7. Actions on Objectives: In the final phase, the attacker takes steps to achieve their ultimate goals, which can vary widely. Objectives might include data theft, espionage, data destruction, or disruption of services. The attacker may move laterally within the network, escalate privileges, and target additional systems to maximize their impact.

The cyber kill chain model is valuable for several reasons. It provides a structured approach to understanding and dissecting cyber attacks, enabling defenders to anticipate and disrupt each stage of the attack. By identifying specific actions and behaviors associated with each phase, security teams can implement targeted defenses and detection mechanisms.

For example, during the reconnaissance phase, defenders can monitor for unusual scanning activities. In the delivery phase, they can employ email filtering and URL blacklisting. During the installation phase, endpoint protection software can detect and block the installation of backdoors.

The model also emphasizes the importance of defense-in-depth, where multiple layers of security controls are implemented to protect against attacks at various stages of the kill chain. This approach reduces the likelihood of a successful attack and increases the chances of detecting and mitigating threats early.

In summary, the cyber attack kill chain is a critical framework for understanding, detecting, and defending against cyber threats. By breaking down the complex process of a cyber attack into manageable stages, it provides a roadmap for effective cybersecurity strategies and defenses.

For further reading, you can explore resources like the Lockheed Martin Cyber Kill Chain and SANS Institute's guide on cyber kill chains.

In the Wild

A real-world example of a cyber kill chain is the 2014 Sony Pictures hack. The attackers, allegedly from North Korea, conducted reconnaissance by researching Sony's network and employees. They weaponized a malware package, including a destructive wiper.

The delivery occurred via spear-phishing emails. Upon opening, the malware exploited system vulnerabilities (exploitation). The attackers installed the malware to maintain access (installation). They established command and control channels to communicate with compromised systems.

Finally, in the actions on objectives phase, they stole confidential data and released it publicly, causing significant damage to Sony's reputation and operations.