The ScarCruft Korean-speaking APT is changing up its espionage tactics to include an unusual piece of malware devoted to harvesting Bluetooth information – while also showing some overlap with the DarkHotel APT.
An analysis of ScarCruft’s binary infection procedure by Kaspersky Lab shows that in a campaign that continued over the course of 2018, the group used a multi-stage process to update each of its malware modules effectively while also evading detection.
The researchers said that spear-phishing and the use of various public exploits remain ScarCruft’s go-to initial attack vectors. Once the victim is compromised, the attack installs an initial dropper, which uses a known exploit for CVE-2018-8120 to bypass Windows User Account Control (UAC) in order to execute the next payload, a downloader, with higher privileges. This stage connects with the command-and-control (C2) server to grab the next payload, which is hidden in an image using steganography.