A new fileless attack dubbed PyLoose has been observed striking cloud workloads with the goal of delivering a cryptocurrency miner, new findings from Wiz reveal.
“The attack consists of Python code that loads an XMRig Miner directly into memory using memfd, a known Linux fileless technique,” security researchers Avigayil Mechtinger, Oren Ofer, and Itamar Gilad said. “This is the first publicly documented Python-based fileless attack targeting cloud workloads in the wild.”
The cloud security firm said it found nearly 200 instances where the attack method was employed for cryptocurrency mining. No other details about the threat actor are currently known other than the fact that they possess sophisticated capabilities.
In the infection chain documented by Wiz, initial access is achieved through the exploitation of a publicly accessible Jupyter Notebook service that allowed for the execution of system commands using Python modules.
PyLoose, first detected on June 22, 2023, is a Python script with just nine lines of code that embeds a compressed and encoded precompiled XMRig miner. The payload is retrieved from paste.c-net[.]org into the Python runtime’s memory by means of an HTTPS GET request without having to write the file to disk.
images from Hacker News