The state-sponsored North Korean hackers APT37, also known as Ricochet Chollima, target journalists with Goldbackdoor malware.
According to NK News, the malicious software spreads through phishing attacks. Emails to journalists included a link to download ZIP archives of LNK files, both named ‘Kang Min-chol edits.’ Kang Min-chol is North Korea’s Minister of Mining Industries.
The Goldbackdoor malware runs as a PE file (portable executable) and can remotely accept basic commands and exfiltrate data. It also has a number of API keys that can be used to authenticate to Azure and recover commands to execute.
To exfiltrate files, the malware uses legitimate cloud services such as Google Drive and Microsoft OneDrive. Files targeted by the malware are mainly documents and media such as PDF, DOCX, MP3, TXT, M4A, JPC, XLS, PPT, BIN, 3GP and MSG.
The campaign uses a two-stage infection process that gave the threat actors more deployment versatility. It also made it harder for analysts to capture payloads.