The United States and Canada on Thursday issued a rare joint cyber-alert, warning against a recent surge in extortion attacks that infect computers with viruses known as “ransomware,” which encrypt data and demand payments for…

The United States and Canada on Thursday issued a rare joint cyber-alert, warning against a recent surge in extortion attacks that infect computers with viruses known as “ransomware,” which encrypt data and demand payments for…
The first known ransomware attack on Apple’s Mac computers, which was discovered over the weekend, was downloaded more than 6,000 times before the threat was contained, according to a developer whose product was tainted with…