iPhone hacking expert, Zdziarski, had revealed during a forensic seminar about cracking iPhone's passcode that iPhone takes screen shots every time you push your iPhone's home button.
As per Zdziarski, the iPhone takes the screen shot for the 3D "zoom" effect that is observed when you close/suspend or launch/resume an iPhone app. This has raised privacy concerns as the screen shots are stored, at least temporarily on the iPhone.
You don't need to be worried as Zdziarski has also figured out a way to disable the storing of the screen shots on the iPhone so that they cannot be recovered.
Jonathan Zdziarski better known as “NerveGas” in the iPhone hacking community has published the iPhone Open Application Development book to develop unofficial native iPhone applications using the iPhone open source tool chain and is also the author of iPhone Forensics. He had recently ported the iPhone Open Source Tool chain to iPhone firmware 2.0. Jonathan was the first to develop a native iPhone application that takes full advantage of the major iPhone APIs with NES.app for iPhone firmware 1.x , a portable Nintendo Entertainment System emulator which he has successfully ported to iPhone firmware 2.0. He had recently discovered a remote URL which suggested that Apple has included a kill-switch mechanism in iPhone firmware 2.0 to deactivate malicious iPhone apps already installed on the iPhone during his forensic examination of iPhone 3G. Steve Jobs had later in an interview with Wall Street Journal confirmed the existence of the kill-switch. He has also figured out a way to disable the storing of the screen shots on the iPhone so that they cannot be recovered. He writes:
"I did some further digging and found that the screenshots themselves actually get written to /var/mobile/Library/Caches/Snapshots. If you delete this folder and symlink it to /dev/null, the screenshots don't get written to disk. The side effect to this is that when resuming an application, you'll get the default screen in the zoom-in effect. Once the application resumes, however, you'll have your application screen back. For example, your mail application will always zoom to the front as if you had an empty inbox, but will quickly correct itself once the application resumes. On a jailbroken iPhone, you can disable these screenshots with the following commands:
# rm -rf /var/mobile/Library/Caches/Snapshots
# ln -s /dev/null /var/mobile/Library/Caches/Snapshots
To return to the default behavior, just delete the symlink and the directory will get recreated. Mind you, this has no effect on the many other pieces of data stored on the iPhone, and therefore your iPhone will always be at risk for leaking private data, especially to seasoned forensic examiners."
Interesting stuff, but how many of you are really worried about this and plan to disable it?
[via Zdziarski's blog]
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Did someone lose their Tin Foil Hat? I think I found it.
screeen shot has been there for a while sense 1.1.4
anyone else think this website is starting to get old? Maybe it's just me but more and more lame articles are being thrown on.
You forgot to close the quotation.
It's a conspiracy!
I wonder if this will improve stability?
Hey Jared,
Thanks for your feedback, we will definitely try to do a better job.
Hey Ezea,
Thanks for highlighting the missing quote!
cheers!
i think some people are not reading the post properly because this is not about the screen shot option, this is about every time you exit an applictaion the phone automatically stores shots of your current screen so that it can do that wonderful zoom out thing back to your home screen, eg, if your reading a PRIVATE email and you exit it by pressing the home button, shots of your current email are being tempararily saved to the iphone so that it can do a pretty little zoom out back to your springboard…
@Anonymous Coward
My name is Ezra
Just change the default Password in mobile terminal.
I Remember When "iPhoneHacks" Was About Hacking … Now It's Just Regular Old News That Nobody Really Cares About … Make It About Hacks … Pirating … Not Mainstream !
i don't think that just disabling that will have an impact on performance, 'cause the screen shots are still going to be taken, they won't be saved, but the ipohone is still going to take it. Probably if the function could be disabled at all, it might have a positive performance impact.
I remember when people used to appreciate someone dedicating their time and energy to developing a comprehensive location of iPhone news. iPhoneHacks brings you hacking news when its available… Maybe it is just me. Either way, I would like to give my thanks to iPhoneHacks for all their current, past, and future efforts for the iPhone community.
(Pardon the mocking opening…)
@DrumstaT, thanks for your feedback, we value it a lot.
@Niik09, thanks for your support.
You are right, we are not just trying to bring Hacking news but everything interesting related to the iPhone because we are iPhone fanboys just like you and like sharing things that we find interesting and would be helpful for our readers.
I agree we have been slower in bringing real-time news lately. Unfortunately due to the day job it becomes difficult to bring more iPhone related stuff to you folks. We will try to address that situation soon.
Thanks for all your comments and keep them coming.
cheers!
I think you guys are doing a great job. I check this blog everyday. BTW, everyday news relates to hacking. Stories about iPhone apps being rejected by Apple, and loopholes in ad hoc distribution interest me as much as hearing about the latest hackery. Keep up the good work iphonehacks team!
Fully agree with Andrew D! Just keep going …