Cybersecurity researchers are calling consideration to a brand new subtle malware referred to as CoffeeLoader that is designed to obtain and execute secondary payloads.
The malware, in accordance with Zscaler ThreatLabz, shares behavioral similarities with one other recognized malware loader generally known as SmokeLoader.
“The aim of the malware is to obtain and execute second-stage payloads whereas evading detection by endpoint-based safety merchandise,” Brett Stone-Gross, senior director of risk intelligence at Zscaler, stated in a technical write-up printed this week.
“The malware makes use of quite a few methods to bypass safety options, together with a specialised packer that makes use of the GPU, name stack spoofing, sleep obfuscation, and the usage of Home windows fibers.”
CoffeeLoader, which originated round September 2024, leverages a website technology algorithm (DGA) as a fallback mechanism in case the first command-and-control (C2) channels change into unreachable.
Central to the malware is a packer dubbed Armoury that executes code on a system’s GPU to complicate evaluation in digital environments. It has been so named attributable to the truth that it impersonates the authentic Armoury Crate utility developed by ASUS.
The an infection sequence begins with a dropper that, amongst different issues, makes an attempt to execute a DLL payload packed by Armoury (“ArmouryAIOSDK.dll” or “ArmouryA.dll”) with elevated privileges, however not earlier than trying to bypass Consumer Account Management (UAC) if the dropper doesn’t have the required permissions.
The dropper can also be designed to ascertain persistence on the host by way of a scheduled process that is configured to run both upon consumer logon with the best run degree or each 10 minutes. This step is succeeded by the execution of a stager part that, in flip, hundreds the principle module.
“The primary module implements quite a few methods to evade detection by antivirus (AV) and Endpoint Detection and Response (EDRs) together with name stack spoofing, sleep obfuscation, and leveraging Home windows Fibers,” Stone-Gross stated.
These strategies are able to faking a name stack to obscure the origin of a perform name and obfuscating the payload whereas it’s in a sleep state, thereby permitting it to sidestep detection by safety software program.
The final word goal of CoffeeLoader is to contact a C2 server by way of HTTPS with the intention to acquire the next-stage malware. This consists of instructions to inject and execute Rhadamanthys shellcode.
Zscaler stated it recognized quite a lot of commonalities between CoffeeLoader and SmokeLoader on the supply code degree, elevating the likelihood that it might be the following main iteration of the latter, significantly within the aftermath of a regulation enforcement effort final yr that took down its infrastructure.
“There are additionally notable similarities between SmokeLoader and CoffeeLoader, with the previous distributing the latter, however the precise relationship between the 2 malware households just isn’t but clear,” the corporate stated.
The event comes as Seqrite Labs detailed a phishing electronic mail marketing campaign to kickstart a multi-stage an infection chain that drops an information-stealing malware referred to as Snake Keylogger.
It additionally follows one other cluster of exercise that has focused customers participating in cryptocurrency buying and selling by way of Reddit posts promoting cracked variations of TradingView to trick customers into putting in stealers like Lumma and Atomic on Home windows and macOS techniques.