Less than 24 hours after admitting some of its employees computers had been hacked, Apple has pushed out a security update to users of its Mac computers, according to BBC News.

The patch fixes issues surrounding Java, a popular programming language that had a major security hole allowing malicious code to infect machines.

Apple was among several companies targeted in recent weeks by hackers exploiting the Java weakness.

Both Facebook and Twitter have made recent admissions of being hacked - with Twitter having to email thousands of users with instructions on how to reset their passwords.

In statement, Apple made a rare admission of a breach.

"We identified a small number of systems within Apple that were infected and isolated them from our network," the company said. "There is no evidence that any data left Apple. We are working closely with law enforcement to find the source of the malware."

The iPhone-maker went on to say it would be releasing a security patch - which it has now done. Users will be automatically informed about the update.