Cybersecurity researchers say a new ransomware campaign is exploiting an undisclosed zero-day vulnerability and hitting hospitals and clinics across several countries. The attacks have reportedly led to data breaches and temporary service disruptions, raising concerns about patient care and the security of sensitive medical records.

According to the report, the campaign is affecting healthcare organizations worldwide, with multiple nations seeing incidents in the past hour. Researchers have not publicly identified the flaw, but the use of a zero-day means attackers appear to have moved before defenders could patch the weakness.

Healthcare systems are frequent targets for ransomware because outages can force administrators to choose between restoring operations quickly and refusing ransom demands. When patient data and essential services are at stake, the impact can extend far beyond IT departments and into emergency rooms, clinics, and public health networks.

Security teams are urging hospitals to isolate affected systems, strengthen monitoring, and apply defensive measures as updates become available. The latest wave underscores how quickly criminal groups can turn an unknown software flaw into a global crisis for civilian infrastructure.