A software bug in Apple's iOS software was exposed, allowing iPad and iPhone owners to modify the iOS operating system.

The website www.jailbreakme.com web site released a code that Apple customers can use to "jail break" their Apple devices. This would allow them to download and run applications that are not approved by Apple or use iPhone phones on networks of carriers that are not approved by Apple.

Dubbed "JailbreakMe", the code is described as "the easiest way to free your device," allowing iPAd and iPhone owners to "experience iOS as it could be, fully customizable, themeable, and with every tweak they could possibly imagine."

According to the hackers, the code is completely reversible, meaning that if a user decides to undo the jailbreak.

However, security experts warned that criminal hackers could download the JailbreakMe code, reverse engineer it to identify a hole in iOS security and build a piece of malicious software.

Apple has been vocal against jail breaking, which if done voids the warranty on its devices.

The company is expected to issue a patch before anybody exploited the bug for malicious purposes.