Mustang Panda Upgrades CoolClient With a Kernel Rootkit
Mustang Panda's updated CoolClient backdoor deploys a signed kernel driver to hide processes, files and network activity in Asian intrusions.
Kaspersky analysis shows Mustang Panda (HoneyMyte) upgraded its CoolClient espionage backdoor with a signed kernel-mode driver installed as a Windows service, communicating via IOCTL requests to hide processes, files and registry entries. In a Myanmar campaign the actor deployed PlugX first, then CoolClient via a fake Windows Defender directory and Sangfor defender.exe DLL sideloading, with scheduled task and AutoRun persistence and UAC bypass. The updated variant was observed in intrusions across Pakistan, Mongolia and Myanmar, with victims also in Russia including confirmed government entities.