Following reports of a new worm that could impact some jailbroken iPhones, Apple offered up a response: hacking your iPhone is a bad idea.

Jailbreaking is a process where users apply software hacks to their iPhone or iPod touch to allow the installation of applications that aren't available through Apple's iTunes-based App Store.

The most recent threat works only on iPhones that have been hacked to support unauthorized third-party applications, have SSH installed, and are still using the default root password. The worm spreads between iPhones that are on the same Wi-Fi network, and targets ING Bank Web site users in the Netherlands.

"As we've said before, the vast majority of customers do not jailbreak their iPhones, and for good reason," Apple spokesperson Natalie Harrison told The Loop. "These hacks not only violate the warranty, they will also cause the iPhone to become unstable and not work reliably."

Apple may not have come right out and said hacking an iPhone to run software that isn't available through its App Store is a bad idea, other security companies have.

"We would like to stress that users who jailbreak their iPhones are exposing themselves to known vulnerabilities that are being exploited by code that is circulating in the wild," Intego said after an attack that could let a hacker download iPhone user data surfaced. "While the number of iPhones attacked may be minimal, the amount of personal data that can be compromised strongly suggests that iPhone users should stick with their stock configuration and not jailbreak their devices."

Apple didn't say whether or not it is working on ways to improve security for jailbroken iPhones, but since the company considers the hacks unauthorized, it's likely those users could find themselves on their own.