Storm-0842

Group-IB Uncovers HEAVYGRAM Multi-Stage Windows Spyware Controlled via Telegram Bot API

Researchers at Group-IB have identified 29 new samples of HEAVYGRAM, a sophisticated multi-stage Windows malware designed to target journalists, Iranian dissidents, and government critics. The campaign begins with social engineering lures that deliver archives containing fake Telegram, KeePass, or video editor files, along with WSF, HTA, and Persian-language screensaver payloads. Once executed, the malware uses PowerShell to fetch additional components, establishes persistence through Windows startup mechanisms, and adds its directories to Microsoft Defender exclusions. The core implant, written in Python and packed with PyInstaller, supports DLL side-loading and communicates exclusively through Telegram Bot API to receive commands, capture screenshots, enumerate processes, and exfiltrate data. A particularly damaging capability allows theft of Telegram Desktop session files, enabling account hijacking without password re-entry. Group-IB attributes the operation to the Handala Hack group, linked to the Void Manticore persona also tracked as Storm-0842 and Red Sandstorm, believed to operate on behalf of Iranian intelligence services.