Symantec has identified a proof-of-concept virus, OSX.Macarena, which it claims offers a "very low" level of risk.
The virus was identified 2 November. The company describes the virus as: "A proof-of-concept virus that infects files in the current folder on the compromised computer."
The virus carries no payload - it simply exists to replicate iteself. Once it is launched it infects every file contained in the same folder. The company has identified just 50 instances of systems being infected by Macarena.
"It won't replicate very well, because it is restricted to the current directory," observes Symantec's Peter Ferrie on his blog.
"If you have read the OSX/Leap paper from this year's Virus Bulletin conference, you will have seen some suggestions about possible infection methods. Those suggestions were all ignored by the virus author in this case. Instead, the virus writer has found a rather unexpected region of memory in which to place the code, along with a way to gain immediate control when an infected file is executed," he adds.