Apple said the update released for OS X Lion, Mountain Lion, and Mavericks versions of its computer operating software patch a Unix shell flaw billed as a dangerous weakness that could be exploited by hackers.
Even though the flaw was found in Unix-based Mac OS and Linux operating systems, most users of Apple computers were believed to have been protected due to default settings in the software running Macintosh machines, according to the California-based company.
"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 last week.
"With OS X, systems are safe by default and not exposed to remote exploits of Bash unless users configure advanced Unix services."
The US government and technology experts last week 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 personal computers 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."
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