Mac users are once again being urged to exercise caution when installing updates to Adobe Flash Player, after a fake update was discovered infecting computers.Intego security experts have identified the rogue package installer as a variant of OSX/InstallCore, and have updated Intego VirusBarrier definitions to provide protection.The in-the-wild attack has been spread in the form of a Mac Package installer .pkg file, also known a flat package, and has been signed with a legitimate Developer ID certificate — effectively tricking OS X's built-in Gatekeeper security to believe that the files can be trusted and are not malicious.Curiously, if the Mac Package...