The Computer Emergency Response Team of Ukraine (CERT-UA) has issued a cautionary alert regarding a series of cyber assaults aimed at the country’s defense forces. These attacks, part of an espionage operation dubbed SickSync, employ a malware strain known as SPECTR. CERT-UA attributes these malicious activities to a threat actor identified as UAC-0020, also known as Vermin, purportedly linked to the security agencies of the Luhansk People’s Republic (LPR).
The attack vectors initiated by SickSync typically commence with targeted spear-phishing campaigns, wherein recipients receive deceptive emails containing a RAR self-extracting archive file. This archive conceals a decoy PDF file alongside a trojanized version of the SyncThing application, which harbors the SPECTR payload. Upon execution, a batch script activates the infection process by launching the executable, initiating the malware’s operations.
SPECTR, serving as an information-stealing tool, conducts a broad array of intrusive actions upon compromising a system. It is equipped to capture screenshots at regular intervals, harvest files, extract data from removable USB drives, and pilfer credentials from various sources, including web browsers and communication applications like Element, Signal, Skype, and Telegram. CERT-UA notes that the attackers exploit the legitimate synchronization functionality of SyncThing to facilitate the exfiltration of stolen data, establishing peer-to-peer connections between compromised systems for data transfer.
The resurgence of the Vermin group, observed after a period of dormancy, signals a renewed wave of cyber threats targeting Ukrainian entities. Previously, in March 2022, Vermin orchestrated phishing campaigns aimed at state bodies in Ukraine, deploying the SPECTR malware. This malware strain, known to have been active since 2019, has long been associated with Vermin’s cyber operations. Additionally, Vermin is also linked to a .NET remote access trojan, first documented by Palo Alto Networks Unit 42 in 2018, which has targeted Ukrainian government institutions for nearly eight years.
Furthermore, CERT-UA’s alert coincides with warnings about social engineering attacks leveraging the Signal messaging app to distribute the DarkCrystal RAT (aka DCRat). These activities, attributed to the UAC-0200 cluster, underscore a trend of escalating cyber threats utilizing messaging platforms as distribution vectors. The advisory also follows the discovery of a malware campaign conducted by Belarusian state-sponsored hackers, known as GhostWriter, targeting the Ukrainian Ministry of Defense with booby-trapped Microsoft Excel documents.
