North Korean threat actors, tracked under the codenames Contagious Interview and Wagemole, have been implicated in two distinct cyber campaigns involving masquerading as job recruiters and seekers. The Contagious Interview campaign aims to infect software developers through fictitious job interviews, introducing cross-platform malware named BeaverTail and InvisibleFerret.
BeaverTail is a JavaScript implant functioning as a stealer and loader, capable of extracting sensitive information from web browsers and crypto wallets. InvisibleFerret, a Python-based backdoor with diverse functionalities, including remote control, keylogging, and data exfiltration, is part of this campaign.
On the other front, the Wagemole campaign is designed for financial gain and espionage, utilizing fraudulent job-seeking activities via GitHub repositories with forged identities, creating opportunities to embed insiders within targeted organizations. The campaign reflects the broader concern of fraudulent job offers and the vulnerability of software developers to supply chain attacks.
The Contagious Interview attacks present a sophisticated tactic where threat actors use fictitious job interviews to introduce previously undocumented malware capable of running on Windows, Linux, and macOS systems. The malware, BeaverTail and InvisibleFerret, are adept at stealing sensitive information and establishing remote control access, demonstrating the evolving tactics of North Korean threat actors.
The involvement of North Korea in such cyber campaigns aligns with its historical subterfuge efforts to beat sanctions, as disclosed in a recent U.S. government advisory. These campaigns underscore the significance of ongoing concerns about fraudulent job offers and the exploitation of software developers, highlighting the need for vigilance and cybersecurity measures in the face of sophisticated threats.
Unit 42’s analysis reveals tactical overlaps with previous North Korean threat activities, such as Operation Dream Job, emphasizing a pattern of approaching employees with enticing job offers that conceal malicious payloads. The report suggests that software developers, often considered a weak link in supply chain attacks, are particularly vulnerable to such tactics.
The extensive use of well-maintained GitHub repositories, complete with LinkedIn profiles, indicates a high level of sophistication, making it challenging to distinguish these accounts from legitimate ones. The campaigns exemplify the persistent threat landscape where actors like North Korea continue to exploit innovative methods, such as fake job offers, to achieve their strategic goals, posing challenges for organizations and emphasizing the need for ongoing cybersecurity efforts.
