The BlueNoroff APT group, which is linked to North Korea’s notorious Lazarus group, has been spotted targeting Mac users with a new malware family called RustBucket.
Security firm Jamf discovered the malware, which allows operators to download and execute various payloads. The group is believed to be responsible for the SnatchCrypto campaign, in which they created numerous fake domains impersonating venture capital firms and banks.
Furthermore, the RustBucket malware was contained within an unsigned application called Internal PDF Viewer.app, which experts believe can only be executed by manually overriding the Gatekeeper security measure.
Upon executing, the malware collects system information, including the process listing, current time and whether or not it’s running within a virtual machine (VM). The third-stage payload allows the attacker to carry out a broad range of malicious activities on the system.
Jamf’s analysis shows that the Internal PDF Viewer application appears to be a functional PDF viewer, but is, in fact, a Trojan. The similarities in the findings between the RustBucket malware and those of Kaspersky’s analysis published in December 2022 allowed researchers to attribute the malware to the BlueNoroff APT.
The use of fake domains impersonating venture capital firms and banks and social engineering tactics observed by Jamf led the experts into attributing the attacks to BlueNoroff.
As macOS grows in market share, attackers are becoming more aware that some victims will be immune if their tooling is not updated to include the Apple ecosystem.
With its long history of attacking macOS, it is likely that more APT groups, like Lazarus and BlueNoroff, will follow suit.
