On August 25, 2021, the FBI issued a Flash Alert to warn companies, especially in the health care industry, about the proliferation of attacks by threat actors using Hive ransomware.

According to the Flash Alert, Hive was first observed in June 2021: “Hive ransomware uses multiple mechanisms to compromise business networks, including phishing emails with malicious attachments to gain access and Remote Desktop Protocol (RDP) to move laterally once on the network.”

“After compromising a victim network, Hive ransomware actors exfiltrate data and encrypt files on the network. The actors leave a ransom note in each affected directory within a victim’s system, which provides instructions on how to purchase the decryption software. The ransom note also threatens to leak exfiltrated victim data on the Tor site, ‘HiveLeaks.'”

The Flash Warning provides technical details, indicators of compromise, the content of a sample ransom note, and recommended mitigation techniques. The FBI also requests that all victims provide information to the FBI if they have suffered an attack using Hive.