A ransomware breach of a little-known computer network has shut down a key technical tool that the U.S. Marshals use to hunt fugitives via their cellphones.

Prospect Medical Holdings, a chain that owns hospitals, as well as more than 165 outpatient facilities, said ransomware hackers had breached its system.

A second cyber incident at data provider CDK Global, whose software is used at 15,000 auto dealers, continued to slow operations to a near-standstill Thursday at US and Canada dealerships, the ...

Hundreds of United Airlines flights were disrupted on Wednesday evening as the carrier grappled with a major computer system outage. The airline requested ground stops at its major hubs in the U.S.

Federal officials are scrambling to assess the damage and address flaws in a sprawling, heavily used computer system long known to have vulnerabilities.