A dangerous ransomware program has taken data from hundreds of victims hostage—and more could be at risk, according to a warning from multiple federal agencies. Medusa, a ransomware-as-a-service variant,

The FBI has issued a warning about ransomware threats targeting the United States Postal Service and Gmail and Outlook users. According to the agency, the Medusa ransomware gang—an organization that has been active since 2022—is behind the attacks.

The FBI, MS-ISAC and CISA released a joint cybersecurity advisory about the Medusa ransomware variant, advising people and organizations to use multifactor authentication and other strategies to prevent attacks from the ransomware-as-a-service provider that has targeted hundreds since 2021.