Security researchers have spotted signs of the Necro Python botnet targeting a vulnerability in Visual Tools DVR systems to install a Monero miner on infected systems.
First discovered in January this year, Necro Python is also tracked as N3Cr0m0rPh, FreakOut, Python.IRCBot and is known for attempting to exploit multiple known vulnerabilities.
In late September, the botnet added to its arsenal an exploit targeting a security vulnerability in Visual Tools DVR VX16 126.96.36.199, according to a warning from Juniper Threat Labs.
Based on Python, the botnet includes a broad range of capabilities, including the ability to sniff network traffic, launch distributed denial of service attacks, infect different types of files (HTML, JS, PHP), install a Monero miner, execute commands, and spread using exploits or brute-forcing.
What’s more, although it emerged in January as a piece of malware targeting Linux systems, the script can run on Windows systems as well and can install a Windows rootkit.
“The script has its own polymorphic engine to morph itself every execution which can bypass signature-based defenses. This works by reading every string in its code and encrypting it using a hardcoded key,” the researchers explain.
The botnet uses a Domain Generation Algorithm (DGA) for both its command and control (C&C) and download server. Once connected to the C&C, it can scan IPs, add/remove ports from the scanner, launch a reverse shell, execute files, kill processes, update itself, launch UDP/SYN/TCP floods, launch amplification/reflection attacks, and more.
Since January, the botnet has received several updates, including the implementation of new exploits and the addition/removal of features (a SMB scanner observed in May has been removed in the latest version).
The latest exploit added to its arsenal is based on proof-of-concept code that was made publicly available in July 2021. Prior to launching the attack, the malware scans for open ports 22, 80, 443, 8081, 8081, and 7001.