Apple just updated XProtect - its malware and virus protection system - to block an attack that has already infected thousands of Macs.
Dr. Web, a Russian antivirus firm, reported the emergence of this troublesome malware network that specifically goes after Apple Mac computers. The malware, called iWorm, disguises itself in a Java application and and automatically launches on infected machines.
Beginning Saturday, Apple updated XProtect to detect and defend against three versions of iWorm.
It remains an mystery how the malware's creators spread iWorm, but it does include an interesting feature. It actually enlists infected Macs in the botnet (a collection of internet-connected programs that communicate with others to perform tasks) by use of a Reddit search. Basically, this search returns a list of botnet servers that an infected machine could connect with. Once a connection has been made, it waits for instructions from iWorm operators.