In the latest update to Snow Leopard, Apple included software to protect Mac computers from a Trojan horse that has been distributed by attackers disguised as iPhoto, but which opens a back door on the machine, security firm Sophos said on Friday.
When Apple released OS X 10.6.4 on Tuesday, the company said it addressed certain compatibility issues with VPN connections and other things, but failed to mention anything about adding an anti-malware update.
But buried in the code is an update to the XProtect.plist file, which contains signatures of malware written to target the Mac. The signatures now detect malware dubbed "HellRTS," Graham Clulely of Sophos wrote in a blog post.
For more on this story, read Apple quietly adds anti-malware in Snow Leopard update on CNET News.