Last Updated: 2022-06-24 05:13:38 UTC
by Xavier Mertens (Version: 1)
A quick diary to wrap-up the week with a nice Python script that interacts with the victim. Most malicious scripts try to remain below the radar to perform their nasty tasks. I found a Python script that has some interesting features. The file has a VT score of 10/55 (SHA256:e21f6c09fb1658397d0996751f4c79114f50a0853668227c1c589fb716b31603). The core feature is this script is to implement a keylogger but it has interesting capabilities.
First, it retrieves its C2 server via a simple HTTP request and extract it from the returned HTML code:
The protocol implemented with the C2 servers is very simple and seems to be "homemade", just a TCP session waiting for commands based on single letters:
There are classic commands to start/stop the keylogger, to upload/download files but you can also interact with the Windows 10 GUI. There is an interesting Python module loaded: "win10toast_click". This module helps to display Windows Toast notifications like this example:
Here is the code used by the malicious script:
The attacker will display a notification to the victim and, if clicked, a browser will be launched with a (probably malicious) webpage with the help of the web-browser module. This is perfect to conduct social engineering attacks and, for example, ask the user to leave credentials on a rogue site.
Xavier Mertens (@xme)
Senior ISC Handler - Freelance Cyber Security Consultant