The Raspberry Robin worm has been utilized in assaults in opposition to telecommunications and authorities workplace methods throughout Latin America, Australia, and Europe since a minimum of September 2022.
“The principle payload itself is filled with greater than 10 layers for obfuscation and is able to delivering a pretend payload as soon as it detects sandboxing and safety analytics instruments,” Pattern Micro researcher Christopher So said in a technical evaluation printed Tuesday.
A majority of the infections have been detected in Argentina, adopted by Australia, Mexico, Croatia, Italy, Brazil, France, India, and Colombia.
Raspberry Robin, attributed to an exercise cluster tracked by Microsoft as DEV-0856, is being more and more leveraged by multiple threat actors as an preliminary entry mechanism to ship payloads corresponding to LockBit and Clop ransomware.
The malware is understood for counting on contaminated USB drives as a distribution vector to obtain a rogue MSI installer file that deploys the primary payload liable for facilitating post-exploitation.
Additional evaluation of Raspberry Robin reveals using heavy obfuscation to stop evaluation, with the malware “composed of two payloads embedded in a payload loader packed six instances.”
The payload loader, for its half, is orchestrated to load the decoy payload, an adware dubbed BrowserAssistant, to throw off detection efforts.
Ought to no sandboxing and evaluation be noticed, the reliable payload is put in and proceeds to hook up with a hard-coded .onion tackle utilizing a customized TOR shopper embedded inside it to await additional instructions.
The TOR shopper course of masquerades as reliable Home windows processes like dllhost.exe, regsvr32.exe, and rundll32.exe, as soon as once more underscoring the appreciable efforts made by the menace actor to fly underneath the radar.
What’s extra, the malware’s actual routine is run in Session 0, a specialized Windows session reserved for companies and different non-interactive consumer purposes to mitigate safety dangers corresponding to shatter attacks.
Pattern Micro mentioned it discovered similarities in a privilege escalation and an anti-debugging approach utilized by Raspberry Robin and LockBit ransomware, hinting at a possible connection between the 2 felony actors.
“The group behind Raspberry Robin is the maker of among the instruments LockBit can be utilizing,” the corporate theorized, including it alternatively “availed of the companies of the affiliate liable for the methods utilized by LockBit.”
That having mentioned, the intrusions look like a reconnaissance operation, as no information is returned from the TOR area, suggesting that the group behind the malware is “testing the waters to see how far its deployments can unfold.”