Patching matters—but so does stopping attackers from moving freely once they get in A new CISA update says Medusa ransomware has affected more than 500 organizations across healthcare, manufacturing, government, and other critical sectors. Janus explains how microsegmentation and least privilege can contain lateral movement. On August 18, 2026, CISA, the FBI, and HHS updated their joint advisory. As of April 2026, Medusa-linked actors had affected more than 500 organizations