The Cactus Ransomware Group Targets ISC Consulting Engineering

The Cactus ransomware group has announced an attack against ISC Consulting Engineering. The group disclosed no further information. ISC Consulting Engineering offers independent engineering consultancy services within all areas of renewable energy, infrastructure, buildings, industry, and oil & gas.

Cactus has been in operation since at least March 2023. Cactus has been observed employing known vulnerabilities within VPN appliances to initiate an initial breach. Once gaining entry to the network, Cactus operators engage in activities such as enumerating local and network user accounts and identifying accessible endpoints. They then proceed to generate new user accounts and utilize custom scripts for the automated rollout and activation of the ransomware encryptor through scheduled tasks.

It is noteworthy that the ransomware encryptor utilized by Cactus exhibits a unique characteristic – it necessitates a decryption key for the execution of the binary, likely implemented to evade detection by anti-virus software. This decryption key is concealed within a file containing random text named ntuser.dat, which is loaded through a scheduled task.