导读： ipad的四位数字密码原本是用来防止别人窥视你的私人信息。但是如今，由于ios 5系统的一个小失误，可能导致这些密码不再具有防护功能。黑客们只需要一个磁智能机盖，就可以“愚弄”ipad，方便地躲过密码输入过程。
The four-digit password code on Apple's iPads is designed to prevent unwanted eyes viewing your personal data.
But a glitch in iOS 5 could mean that the password lock offers no protection at all.
All the hacker requires is a magnetic Smart Cover - either yours, or if you don't use Apple's magnetic screen protector, they can bring their own.
Smart Cover is magnetic, and the iPad's screen 'senses' whether it's closed or open, and turns on accordingly.
It's this automatic 'On' button that can be used to gain access to locked iPad 2s without knowing the password.
In a blog post, Mac fan site 9to5Mac demonstrated that it is possible to gain access to applications such as Mail or messaging simply by turning the targeted iPad off, closing and then opening the Smart Cover, then pressing cancel.
The hack 'fools' iPad into opening up without requiring a password.
At present, the hack is only confirmed to work with the new iOS 5, released last week, but other reports state that it also works on older devices running iOS 4.
At that point, the hacker will not have full access to the device, but will be able to access the last application you had open before you set the lock.
For many users, that application will be Mail - which gives potential attackers access to a huge amount of private information often including bank details and addresses, searchable via the application.
At present, Apple hasn't offered an official 'fix' for the glitch, but 9to5Mac suggests that users can disable Smart Cover unlocking via the Settings menu to ensure that their device is secure.