New BOLDMOVE Backdoor uses FortiOS vulnerability for initial access

A suspected China-nexus campaign has exploited a vulnerability in Fortinet’s FortiOS SSL-VPN, known as CVE-2022-42475. The exploitation was believed to have occurred as early as October 2022 and the targets include a European government entity and a managed service provider in Africa. The malware used in the attack has been identified as “BOLDMOVE” is written in C and has both Windows and Linux variants, the latter of which is intended to run (at least in part) on Fortinet devices as it reads data from a file that is proprietary to Fortinet.