Analysis reveals HEAVYGRAM, a multi-stage Windows backdoor attributed to Iran-linked threat actor Handala Hack, deployed since Fall 2023 targeting Iranian dissidents, journalists, and government opponents. The surveillance tool uses Telegram bot API for command-and-control operations, enabling remote command execution, screen capture, data exfiltration, and persistent access. Victims receive social-engineered files masquerading as legitimate applications like Telegram, KeePass, or Pictory. The implant supports DLL side-loading, registry persistence, and system reconnaissance. Infrastructure analysis identified 29 samples utilizing networks of Telegram bots and groups for operations. The malware aligns with activity disclosed by U.S. Department of Justice regarding Iran's Ministry of Intelligence and Security infrastructure seizures, with tradecraft including Vultr Object Storage and Persian-language decoys targeting specific victim profiles including academics and media personnel.
