Process hollowing is a sophisticated malware technique that involves hijacking a legitimate process to execute malicious code, making it challenging for security systems to detect. This technique has been increasingly used by attackers to evade detection and maintain persistence on compromised systems. To prevent process hollowing, it is essential to understand how it works and implement effective security measures. In this article, we will delve into the world of process hollowing, explore its tactics, techniques, and procedures (TTPs), and provide expert tips on how to prevent it.
Understanding Process Hollowing
Process hollowing is a technique used by malware authors to inject malicious code into a legitimate process, creating a hollowed process. This is achieved by suspending a legitimate process, unmapping its memory, and then mapping the malicious code into the process’s memory space. The malicious code is then executed, allowing the attacker to perform various malicious activities, such as data exfiltration, lateral movement, and command and control (C2) communication.
The Windows API is often exploited to achieve process hollowing. Malware authors use functions such as CreateProcess, SuspendThread, and WriteProcessMemory to create, suspend, and inject code into a legitimate process. The Windows API provides a powerful set of functions that can be used for both legitimate and malicious purposes, making it a popular target for attackers.
Process Hollowing TTPs
Attackers use various TTPs to achieve process hollowing. Some common TTPs include:
- Creating a new process in a suspended state using CreateProcess
- Unmapping the legitimate process’s memory using UnmapViewOfFile
- MAPPING the malicious code into the process’s memory space using WriteProcessMemory
- Resuming the suspended process using ResumeThread
| TTP | Description |
|---|---|
| CreateProcess | Creates a new process in a suspended state |
| UnmapViewOfFile | Unmaps the legitimate process's memory |
| WriteProcessMemory | Mappings the malicious code into the process's memory space |
| ResumeThread | Resumes the suspended process |
Prevention Tips
To prevent process hollowing, follow these expert tips:
- Monitor system calls and API requests: Implement a system call monitoring system to detect suspicious activity, such as unusual API requests or system call patterns.
- Implement behavioral detection: Use a behavioral detection system that can identify and block malicious code injection attempts.
- Use memory protection: Implement memory protection mechanisms, such as DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization), to prevent malicious code execution.
- Keep software up-to-date: Ensure that all software, including operating systems and applications, is up-to-date with the latest security patches.
- Use a reputable security solution: Implement a reputable security solution that includes anti-malware, anti-virus, and intrusion detection capabilities.
What is process hollowing?
+Process hollowing is a sophisticated malware technique that involves hijacking a legitimate process to execute malicious code, making it challenging for security systems to detect.
How does process hollowing work?
+Process hollowing works by suspending a legitimate process, unmapping its memory, and then mapping the malicious code into the process’s memory space. The malicious code is then executed, allowing the attacker to perform various malicious activities.
How can I prevent process hollowing?
+To prevent process hollowing, monitor system calls and API requests, implement behavioral detection, use memory protection, keep software up-to-date, and use a reputable security solution.
