Advanced PowerShell Obfuscation Techniques for Hackers

In the second episode of the "PowerShell for Hackers" series, Jacobe explores advanced techniques used by hackers to obfuscate PowerShell to stay under the radar. The main objective of this video is to demonstrate various methods for obtaining a reverse shell, a crucial tool in penetration testing and cybersecurity operations. Jacobe begins by emphasizing the importance of creativity in PowerShell obfuscation. He highlights that certain commands, such as "Invoke-WebRequest" and "Invoke-RestMethod," are often monitored in secure environments.

To bypass these restrictions, he introduces less conventional methods. One of the techniques presented is the use of the "Resolve-DnsName" command to retrieve PowerShell commands from DNS records. Jacobe shows how DNS records can be used to store malicious payloads. By using TXT records, he demonstrates how to extract a PowerShell command and execute it directly. This method is particularly effective because administrators frequently use "Resolve-DnsName" for legitimate tasks, making it difficult to detect its malicious use.

Another innovative technique is the use of "Alternate Data Streams" (ADS) to hide payloads in file metadata. Jacobe explains how to inject a malicious script into a desktop shortcut so that every time the shortcut is used, the script is executed. This method can be used to obtain a reverse shell or perform other malicious actions. The video also covers a steganography method using PNG images. Jacobe presents "Invoke-PixelScript," a technique that allows hiding payloads in the pixels of an image without altering its appearance.

This method is particularly ingenious because it allows storing malicious scripts in images that can be downloaded and executed later. Jacobe mentions that this technique was inspired by a similar method in Python, which he adapted for PowerShell. Finally, Jacobe discusses the practical implications of these techniques. He emphasizes that while these methods are creative and effective, they can still be detected by advanced security solutions like Threat Locker, which uses behavior-based detection to block malicious actions. In conclusion, this video offers a fascinating glimpse into the advanced PowerShell obfuscation techniques used by hackers. It shows how seemingly innocuous commands can be exploited for malicious actions and highlights the importance of creativity and innovation in the field of cybersecurity. To learn more, watch the full video here: https://www.youtube.com/watch?v=t4rpsFt6n08