WASHINGTON (AFP) -- Apple says that its Macintosh PCs are unlikely to be affected by the recently discovered "Bash" bug that could hit millions of computers and other devices connected to the Internet.

Even though the flaw was found in Unix-based Mac OS and Linux operating systems, most users of Apple computers should be protected, the U.S. company said Friday.

"The vast majority of (Macintosh) OS X users are not at risk to recently reported 'Bash' vulnerabilities," an Apple spokesman said in an email to AFP.

"With OS X, systems are safe by default and not exposed to remote exploits of Bash unless users configure advanced Unix services. We are working to quickly provide a software update for our advanced Unix users."

It comes a day after the U.S. government and technology experts warned of a vulnerability in some computer operating systems that could allow widespread and serious attacks by hackers.

Security specialists say that if hackers develop malware to exploit the weakness, millions of Internet-connected devices could be at risk -- from web servers to PCs to routers, as well as any "smart" or wearable electronic devices using the software.

Some said the security hole would be more damaging than the "Heartbleed" bug which affected millions of computers worldwide earlier this year.

Patches were being made available for the flaw, which is also called "Shellshock."