The North Korean advanced persistent threat group Kimsuky has been identified using spear-phishing attacks to deploy a range of backdoors and tools, including AppleSeed, Meterpreter, and TinyNuke, to compromise targeted machines. AhnLab, a South Korea-based cybersecurity company, attributed these activities to Kimsuky, known for its decade-long history of cyber espionage. The group’s notable use of the AppleSeed backdoor has remained consistent over the years, demonstrating a pattern of attack methods that have evolved little in terms of the associated malware.
Kimsuky, which expanded its focus beyond South Korea in 2017, was recently sanctioned by the U.S. government for accumulating intelligence to support North Korea’s strategic objectives. Kimsuky’s espionage campaigns primarily rely on spear-phishing attacks that deliver malicious lure documents, leading to the deployment of various malware families. Among the Windows-based backdoors employed, AppleSeed (JamBog) stands out as a prominent tool used since May 2019 and updated with an Android version.
Additionally, a new Golang variant named AlphaSeed has been identified, incorporating unique features such as communication via the chromedp library. Evidence suggests that Kimsuky has utilized AlphaSeed in attacks since October 2022, often deploying both AppleSeed and AlphaSeed on the same target system using a JavaScript dropper. Beyond these tools, Kimsuky has been observed deploying Meterpreter and VNC malware like TightVNC and TinyNuke, enhancing its capabilities to gain control over compromised systems.
In a separate revelation, cybersecurity firm Nisos discovered online personas on LinkedIn and GitHub, likely used by North Korean IT workers to fraudulently secure remote employment from U.S. companies. These personas, seeking technology-sector positions, aimed to serve as a revenue stream for the regime and contribute to its economic and security priorities. This disclosure adds to the growing concern over North Korean actors employing various tactics, including cyberattacks on blockchain and cryptocurrency firms, to steal intellectual property and virtual assets, highlighting the country’s determined cyber capabilities despite international sanctions.
