Cybersecurity researchers have discovered a new type of macOS malware called TodoSwift that they say shares common features with known malware used by North Korean hacking groups.
“This app has some behavior associated with malware we’ve seen originating from North Korea (DPRK) — specifically a threat known as BlueNoroff — such as CANDY CORN and RustBucket“, Kandi security researcher Christopher Lopez said in the analysis.
RustBucket, which first appeared in July 2023, refers to an AppleScript-based backdoor capable of receiving next-stage payloads from a Command and Control (C2) server.
Late last year, Elastic Security Labs also discovered another macOS malware, tracked as KANDYKORN, which was deployed in connection with a cyber attack targeting the blockchain engineers of an unnamed cryptocurrency exchange platform.
Delivered via a complex multi-step infection chain, KANDYKORN has the ability to access and steal data from a victim’s computer. It is also designed to terminate arbitrary processes and execute commands on the host.
The common feature that connects c two families of malware is to use linkpc(.)net domains for C2 purposes. Both RustBucket and KANDYKORN are believed to be the work of a hacking group called the Lazarus Group (and its subcluster known as BlueNoroff).
“The DPRK, through entities such as the Lazarus Group, continues to attack crypto-industry businesses to steal cryptocurrency to circumvent international sanctions that hinder their economic growth and ambitions,” Elastic said at the time.
“In this invasion, they targeted blockchain engineers working on a public chat server, appealing to their skills and interests with the promise of financial gain.”
Recent findings from Apple’s Device Management and Security Platform reveal that TodoSwift is distributed in the form of TodoTasks, which consists of an eyedropper component.
This module is a GUI application written in SwiftUI that is designed to display a PDF victim with a weapon while secretly downloading and executing the second stage binary, a method also used in RustBucket.
The PDF decoy is an innocuous Bitcoin-related document hosted on Google Drive, while the malicious payload is extracted from an actor-controlled domain (“buy2x(.)com”). Further research into the exact features of the binary is ongoing.
“Using a Google Drive URL and passing a C2 URL as a launch argument to a Level 2 binary is consistent with previous North Korean malware affecting macOS systems,” Lopez said.
