Why Should I Update my iPhone Firmware to iOS 4.0.2?

Apple has released a security fix for iOS 4 and users now have to decide whether or not to install the update. There are pros and cons to installing the update, mostly revolving around whether or not you're interested in jailbreaking your device. The security problem was first discovered and used by the Dev-Team to hack iOS 4 and provide a simple way to jailbreak through the Safari browser.

apple iphone ios 4.0.2 pdf security fix

Now that Apple has released a fix, the developer responsible for the JailbreakMe 2.0 in-browser jailbreak software has made the source code of his exploit public. Let's be clear, the iOS 4.0.2 update will make jailbreaking with JailbreakMe 2.0 impossible, however now that the source code of the jailbreak is public, security threats are bound to multiply.

Until now, the only software taking advantage of the security hole patched by Apple in 4.0.2 was JailbreakMe, but now that the source code is public it's possible that unscrupulous developers could make a malicious program to infiltrate iPhones running earlier firmware versions through the PDF viewer in Safari. The whole key to keeping safe is not opening suspicious or unknown PDF files through the Safari browser on your iPhone.

Ironically, while Apple has not released a PDF security hole fix for earlier devices such as the original iPhone, underground developers have made the patch available to everyone via the Cydia jailbreak app store. In order to jailbreak iOS 4 or 3.x you must use JailbreakMe 2.0, then with an older jailbroken iPhone you can access the security fix for the same exploit the jailbreak uses to gain access to your device.

Similarly, developers have released a jailbreak app called PDF Loading Warner that asks users whether or not they want to load a PDF file in Safari, possibly preventing the execution of malicious code on their devices. Before you can install this warning system you have to make use of the same security hole to jailbreak the iPhone with JailbreakMe 2.0.

So here's the short answer. If you want to jailbreak your iPhone, don't use Apple's official firmware, but take advantage of the PDF security tools available after you jailbreak to help reduce the chances of problems later. If jailbreaking doesn't interest you at this time, definitely install iOS 4.0.2 so you can have a secure device and not worry about any malicious software that comes your way via PDF files.


There is a new better patch available while remaining jail broken.

The fix is installable via Cydia itself now (search for “PDF Patch”).  To test that it’s working properly, visit jailbreakme.com again.  After you slide to jailbreak, you should no longer see a dialog box pop up (you’ll just see the star background).  That means you’re no longer vulnerable!

thanks a lot

More interesting now~~
before i was worried my iphone 4 will be attacked by malicious code as i have
jialbroken my iphone 4 , but now~ i can avoid it by the PDF Loading Warner~
haha~~ thanks, dev-team, you are still my idol. than i can use frash on my iphone 4,
than combining my ANEESOFT iphone Auxiliary tools~~~my iphone 4 is so nice.

can i jailbreak ipod touch with 4.0.2 without computer and how? tks


yes. go to jailbreakme.com on your ipod

no. it won't work with 4.0.2

how about they figure out the patch to not make iOS4 lag and run so slowly on the 3G. I'm not upgrading until the antenna is fixed!

the antenna problem was never very serious, it was more media hype than anything, but apple fully fixed it several weeks ago so it's go to get in line for an iphone 4... wait time is about 3 weeks.

whut do you mean because my iphone is lagging is your antenna messing up or is it the companys signal i need help i dont whant to lose my wifi in my phone

Hi, I updadted to the IOS 4.0.2 Firmware but want to downgrade to the 4.0.1 again, I have downloaded what I believe to be the Firmware from a couple of websites and they are all the same but I can't find the .IPSW file which I need to restore my phone to. Can someone please help me out with this I am really pulling my hair out.

The best thing to do instead of pulling your hair out is to just wait till they jailbreak 4.0.2, iv done the exact same thing and you can alrealdy jailbreak using redsnOw so i know this reply isnt very helpful but it an option.

So how long as in a random guess will it take dev team to make a jailbreak software program to hack 4.0.2 firmware

That was a very well written article!

i have already jailbroken with blackra1n, if i jailbreak with aanother source (such as JailbreakMe0 will it keep all my files or not? Thx!

is dev team gonna release a jailbreak for version 4.0.2?

I hope they do... Knew nothing about jailbreak till a day after 4.0.2 was installed... Missus never updated it and she got hers jailbroken. Jealous of her now cos she's having more fun with the phone than I am :(

I have an iPhone 3G and I updated the os. It worked fine before but now iTunes says that my sim card is not compatible. Is there any way for me to go back to the prevous version of the iPhone software?

Will it stop freezing phot files were u keep looking and u can't Go back and it freezes u in that album and same with it being slow with youtuve and the 3G not working propranolol
Areas even the provider say it should be good

I am unable to update my 3g iphone to the new ios 4.2 in itunes, I get a message that itunes is current with it's updates 9.2 but nothing about the phone update.

when i update the software, I keep getting this message' the software for the iphone was corrupted during download' any one got a fix for this???