The Stealth Variant of P2Pinfect Botnet Infects MIPS Devices

A new variant of the P2Pinfect botnet has been discovered, targeting devices equipped with MIPS (Microprocessor without Interlocked Pipelined Stages) processors. This latest version of the malware, as reported by Cado Security, is specifically compiled for the MIPS architecture, which is commonly used in routers and IoT devices.

The P2Pinfect botnet, initially identified in July 2023 by Palo Alto Networks' Unit 42, was first known for targeting Redis servers by exploiting a critical Lua sandbox escape vulnerability (CVE-2022-0543). The MIPS variant of P2Pinfect, as observed in Cado Security's honeypots, scans for SSH servers using weak credentials to upload the MIPS binary via SFTP and SCP.

This method of propagation is not limited to SSH, as attempts to run the Redis server on MIPS devices through an OpenWRT package named 'redis-server' have also been spotted. According to Cado Security, the new variant is a 32-bit ELF binary with an embedded 64-bit Windows DLL, enabling shell command execution on the host. This variant of P2Pinfect is particularly concerning due to its sophisticated evasion techniques.

It implements a check for the 'TracerPid' value in the process status file to determine if analysis tools are tracing the malware process and terminates if it is. Additionally, it uses system calls to disable Linux core dumps, preventing the dumping of memory contents that contain traces of its activity.

The report also stated the MIPS sample included a new evasion technique, where the MIPS variant of P2Pinfect could detect if it’s being analyzed and would “immediately terminate both the child process and its parent" to evade detection. The continuous development and expansion of P2Pinfect's targeting scope indicate a high level of coding skills and determination from its authors.

However, the precise objectives of the malware's operators remain uncertain. Potential goals could include cryptocurrency mining, launching DDoS attacks, traffic proxying, or executing data theft. The emergence of the MIPS variant of P2Pinfect marks a significant evolution in cyber threats, particularly for devices with MIPS architecture. The sophistication and stealthiness of this variant underscore the need for heightened vigilance and robust security measures in the cybersecurity landscape.