Description

A Russia-aligned threat actor tracked as UAC-0184 (also known as Hive0156) has been actively targeting Ukrainian military and government entities by abusing the Viber messaging platform to deliver malicious payloads for high-intensity intelligence gathering operations throughout 2025 and into early 2026. Attackers use social engineering and sophisticated multi-stage malware execution to bypass security defenses and gain remote access to compromised systems. The attack leverages the encrypted messaging app Viber as an initial delivery vector, sending victims ZIP archives that contain multiple Windows shortcut files disguised as legitimate Word and Excel documents. When opened, these LNK files display benign decoy content while silently invoking a PowerShell script that retrieves a secondary malicious ZIPfrom a remote server. Within this archive resides Hijack Loader, a stealthy loader that is reconstructed and executed in memory using advanced evasion techniques, such as DLL side-loading and module stomping that attempt to circumvent endpoint detection solutions. Once Hijack Loader gains a foothold, it scans the environment for installed security products by computing CRC32 hashes to tailor evasion. The loader then establishes persistence via scheduled tasks and static signature suppression before deploying the Remcos Remote Access Trojan (RAT) by injecting it into a legitimate process. Remcos grants attackers capabilities including remote command execution, system monitoring, payload deployment, and data exfiltration underpinning the campaign’s espionage objectives.