With the IOS update 4.2.1 is Apple 's product range of mobile devices not only new features donated, but many closed security gaps. Alone has 40 of them were malicious attacker to inject code and execute can abuse. Most of them are in the WebKit Eingine the Safari browser, so that already by visiting a malicious web page in different ways would be to malware can infect. A gap in the presentation of iAd Ads was closed by the attacker on the local network to be found, can initiate calls. A vulnerability in the photo app, attackers can also tap the MobileMe access also.

Against the Limera1nexploit Apple, meanwhile, is powerless: the gap in the boot ROM, the hacker has discovered Geohot and his jailbreak tool uses, Apple can probably by a new boot ROM in upcoming devices connect only. Like the iPhone Dev Team says, can iPhone 3G, 3G and older second-generation iPod touch after updating to 4.2.1 already iOS as usual the unlock. To unlock tools for younger models, the group is working yet. Currently, devices such as the iPad or 4 with iOS iPhone 4.2.1 unlock though, but the modification is not yet permanent and the device, after each restart, for example if the battery was empty, the PC will be connected with (tethered Jailbreak) order mode to start the jailbreak. Also, the Cydia package manager only runs with modifications so that a current device for unlocking hardly worth currently.