APT-C-06 (Darkhotel) is an APT organization that has been active since at least 2007, targeting corporate executives, defense industries, and electronics sectors. In April 2026, the group launched phishing attacks using a decoy document titled 'North Korean Central Television Real-time Broadcasting Program Instructions.' The document instructs users to download an application for watching North Korean Central Television. By late May, attacks evolved to deliver malicious MSI files through phishing emails. These MSI files execute VBS code that creates scheduled tasks to download and execute PowerShell scripts, which then retrieve subsequent payloads. The malware employs ChaCha20 encryption and ultimately deploys shellcode. PowerShell has become a high-frequency component in APT-C-06's attack chain since 2025, handling payload downloads and persistence mechanisms.
The Konni Group conducted a sophisticated multi-stage attack campaign, initiating with a spear-phishing email disguised as a North Korean human rights lecturer appointment. The attack progressed through execution of a malicious LNK file, installation of remote access malware, and long-term persistence for data theft. A key feature was the unauthorized access to victims' KakaoTalk PC applications, used to distribute additional malicious files to selected contacts. The campaign employed multiple RAT families, including EndRAT, RftRAT, and RemcosRAT, with a distributed C2 infrastructure across Finland, Japan, and the Netherlands. The threat actor's tactics included trust-based propagation, account session abuse, and modular payload deployment, highlighting the need for advanced behavior-based detection and multi-layered defense strategies.
