PyXie is a new Remote Access Trojan (RAT), used by cybercrime to steal login credentials, record video. The malware has been seen in conjunction with Cobalt Strike beacons as well as a downloader that has similarities to the Shifu banking Trojan
PyXie is a new Remote Access Trojan (RAT), used by cybercrime to steal login credentials, record video. It also includes a keylogging component to assist in its objectives. It has been discovered by Cylance cyber security experts. The malware has been observed in the wild since at least 2018, but without much attention from the infused community. Now it has been deployed in an ongoing campaign that targets a wide range of industries. It has been seen in conjunction with Cobalt Strike beacons as well as a downloader that has similarities to the Shifu banking Trojan. Analysts have observed evidence of the threat actors attempting to deliver ransomware to the healthcare and education industries with the RAT. Moreover, their developers take a number of steps to obfuscate key components.
How the ongoing PyXie campaign works according the cyber security experts
According the cyber security experts, the key highlights of the PyXie campaign include:
- Legitimate LogMeIn and Google binaries used to sideload payloads.
- A Trojanized Tetris app to load and execute Cobalt Strike stagers from internal network shares.
- Use of a downloader with similarities to Shifu named “Cobalt Mode”.
- Use of Sharphound to collect active directory information from victims.
- A custom compiled Python interpreter that uses scrambled opcodes to hinder analysis.
- Use of a modified RC4 algorithm to encrypt payloads with a unique key per infected host.
The cybercrime campaign uses a side-loading technique leveraging legitimate applications to load the first stage components of the malware. The second stage malware is primarily responsible for installing itself, setting up persistence, and spawning a new process to inject the third stage payload (a downloader designated Cobalt Mode). The final stage payload is a full-featured Python RAT compiled into an executable.