A first-of-its kind piece of malware targeting Macs, Trojan.SMSSend.3666, a fake-installer Trojan for Mac OS X was recently discovered by Russian security firm Dr. Web and subsequently patched by Apple via an update to the Xprotect malware definitions inside each Mac.
Apple has issued a background update (so to speak) which all Macs connected to the Internet received today via the Xprotect mechanism which fights trojans and other types of malware.
A quick visit to /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/XProtect.plist on your Mac will show that Apple has updated the OS X malware definitions to include “SMSSend.”
Anyone mistakenly attempting to install the malware will now get a system warning that will prevent them from getting infected. Apple has acted swiftly this time around, minimizing the risk of infection.
For what it’s worth, you really shouldn’t trust any installation wizard that asks for your phone number (or any other sensitive information).