Users of Apple Computer Inc.'s Macintosh computers have long enjoyed the technology equivalent of a safe neighborhood, where the viruses and security nuisances that bedevil far more common Windows PCs are practically nonexistent. Now, as the Mac is seeing some of its best sales in years, bad guys appear to be casing the joint.
In the past two weeks, information-security companies like Symantec Inc., Sophos PLC and McAfee Inc. have identified several security issues related to the latest version of Apple's Mac operating system, called OS X.
