Cybersecurity agencies in Australia, Canada, New Zealand, and the U.S. have published a joint advisory about the fast flux technique and its associated risks. The technique is being used by hackers to obscure command-and-control (C2) channels. The U.S. Cybersecurity and Infrastructure Security Agency (CISA), National Security Agency (NSA), Federal Bureau of Investigation (FBI) were involved in issuing the advisory. Fast flux involves using multiple IP addresses and rotating between them rapidly. 

Read more: https://thehackernews.com/2025/04/cisa-and-fbi-warn-fast-flux-is-powering.html