MoustachedBouncer is a cyberespionage group discovered by ESET Research and first publicly disclosed in this blogpost. The group has been active since at least 2014 and only targets foreign embassies in Belarus. Since 2020, MoustachedBouncer has most likely been able to perform adversary-in-the-middle (AitM) attacks at the ISP level, within Belarus, in order to compromise its targets. The group uses two separate toolsets that we have named NightClub and Disco.
A large-scale phishing campaign that attempted to target over 10,000 organizations since September 2021 used adversary-in-the-middle (AiTM) phishing sites to steal passwords, hijack a user’s sign-in session, and skip the authentication process, even if the user had enabled multifactor authentication (MFA).