Cybersecurity company Fortinet FTNT.O said Wednesday that it was aware of a "credential-harvesting campaign" targeting its firewall and VPN devices.

In a statement, the company said that hackers were drawing on data "from previous incidents" and "bruteforcing" credentials - describing a process by which hackers throw repeated guesses at a password in order to punch through into a target network or device.

Fortinet said the malicious cyber activity was "not related to any recent incident or advisory."