AntiMalware•September 30, 2026•🇷🇺Translated from Russian

Mimbrob Malware Uses Fake Dronner App to Target Russian Military and Industrial Firms

Cyber-espionage actors have created a website offering a supposedly useful program named Dronner for tracking heavy Baba Yaga drones and remote mining sites. Instead of delivering reconnaissance data, the application installs malicious code. Specialists from F6 discovered the activity and named the operation Mimbrob.

The campaign appears aimed at Russian military personnel who use computers near the line of contact. The application does not function on smartphones. Upon execution, Dronner inspects the system language, keyboard layouts, and preferred interface languages. It targets Russian, several CIS languages, and Romanian. If none of these are detected, the program enters a dormant state for three minutes before terminating itself.

The operators have not limited their activity to military targets. Since April 2026, Mimbrob has attacked Russian industrial enterprises and IT companies through carefully crafted phishing emails. These messages contained fake internal memos about urgent metrological inspections, cooperation proposals, and archives titled “Судебное_разбирательство”. The emails delivered the FBULoader downloader, disguised as a Yandex Browser update, together with the RAT-Go remote access trojan.

Attackers registered domains resembling those of legitimate Russian companies and developers to send the messages. According to F6, the group’s most likely goal is espionage. However, researchers have not yet obtained the final malicious payload, so definitive conclusions about motives remain premature. Technical details and indicators of compromise are published in the F6 report.

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