N. Korea-linked Kimsuky Shifts to Compiled HTML Help Files in Ongoing Cyberattacks
Mar 24, 2024
Artificial Intelligence / Cyber Espionage
The North Korea-linked threat actor known as Kimsuky (aka Black Banshee, Emerald Sleet, or Springtail) has been observed shifting its tactics, leveraging Compiled HTML Help (CHM) files as vectors to deliver malware for harvesting sensitive data. Kimsuky, active since at least 2012, is known to target entities located in South Korea as well as North America, Asia, and Europe. According to Rapid7, attack chains have leveraged weaponized Microsoft Office documents, ISO files, and Windows shortcut (LNK) files, with the group also employing CHM files to deploy malware on compromised hosts . The cybersecurity firm has attributed the activity to Kimsuky with moderate confidence, citing similar tradecraft observed in the past. "While originally designed for help documentation, CHM files have also been exploited for malicious purposes, such as distributing malware, because they can execute JavaScript when opened," the company said . The CHM file is propagated within an IS