Did your iPhone catch the new "Duh" iPhone virus? If so, Apple says it's your own fault for jailbreaking the iPhone. iPhones that have not been jailbroken are not susceptible to the virus, and jailbreakers can take steps to protect themselves.The "Duh" virus is the third to target jailbroken iPhones. In a nutshell, Duh seeks out jailbroken (and vulnerable) iPhones and iPods. Once it locates them, the virus alters the root password of the iPhone or iPod and proceeds to download harmful files to the device. Jailbreaking is the method of unlocking and hacking into the iPhone. It removes a number of controls placed in the device by Apple and permits users to access a much wider range of applications that aren't officially sanction via the iPhone Apps Store.
You can't blame Apple too much for its stance on the recently released virus that attacks iPhones. Apple noted that, "These hacks [jailbreaking] not only violate the warranty, they will also cause the iPhone to become unstable and not work reliably." If you don't jailbreak your iPhone, this virus isn't going to be a problem for you. That means most people (92% - 94%) should be safe.
Because jailbreaking installs SSH networking software, there is a password vulnerability that is easy for viruses to circumvent. There is an easy step to take, however, to a protect jailbroken iPhones. Users can go to Cydia to download and the install the MobileTerminal app. Once that application is installed, users only need to the default password from "alpine" to pretty much anything else.
If you're taking the risk of jailbreaking your iPhone, it isn't that much more work to provide yourself with at least a modicum of safety.