
Newsletter Series: The Cybersecurity Kill Chain
Month 4: Phase 4 – Exploitation: The Attack Begins
After successfully delivering a malicious payload, the attacker now moves to the fourth phase of the Cybersecurity Kill Chain: **Exploitation**. This is when the attack officially begins. The goal is simple - trigger the malicious code and gain control over the target system.
What Happens During Exploitation?
In this phase, the attacker takes advantage of a system vulnerability to execute their code. The exploitation might occur through:
- A user opening a malicious email attachment
- A browser loading a malicious ad or link
- Exploiting an unpatched software vulnerability (like Log4j or EternalBlue)
- Triggering macros embedded in Office documents
At this point, the malware activates, either immediately or on a delay to evade detection. Exploitation is often fast, stealthy and requires no further input from the victim.
Real-World Example:
In the 2017 WannaCry ransomware outbreak, attackers exploited a vulnerability in the Windows SMB protocol. Once the exploit code was executed, WannaCry spread rapidly across networks, encrypting data and demanding ransom - without any user interaction.
How to Prevent Exploitation:
- Apply Security Updates Promptly: Patch known vulnerabilities as soon as updates are released.
- Use Modern Endpoint Protection: Behavioral analysis can detect exploitation even when the
specific malware is unknown.
- Block Macros and Scripts: Disable macros in Office files from unknown sources and restrict
script execution.
- Limit User Privileges: If users don’t have admin rights, exploits are less likely to succeed.
- Run Security Awareness Training: Help staff recognize suspicious documents, links, and
downloads.
Key Takeaway:
The exploitation phase is where an attack goes from theory to reality. Once triggered, the attacker has access to your systems - so stopping them before this point is ideal. But if they succeed, containment and rapid detection are your next best defense.
Next month: The Installation Phase - where the attacker works to ensure long-term access to your environment.
NetCenter Technologies
Empowering Businesses Through Cybersecurity