Malinsure Cybercrime Group Deploys SafeMostSSH Backdoor via Phishing Lures Mimicking Russian Insurance Updates
Researchers from F6 identified a previously unknown cybercrime cluster named Malinsure that has been active since at least July 2026. The group distributes phishing emails containing PDF lures themed around voluntary medical insurance (DMS) discounts and updates from Russian insurance companies. Victims are tricked into downloading RAR or ZIP archives that abuse legitimate Microsoft binaries such as winword.exe and powerpnt.exe through DLL side-loading to execute the custom SafeMostSSH backdoor. The malware establishes a persistent reverse SSH tunnel to attacker-controlled servers and retrieves fresh C2 addresses from public posts on vc.ru by decoding fake PNG links. Additional delivery vectors include HTML and SHTML files that decode and drop archives containing the same payload components. Targets appear to include insurance, finance, and fuel-energy sector organizations, with infrastructure also referencing gosuslugi.email and minfin.support domains.
HabrAug 13, 2026Translated from Russian