Slashdot Mirror
Security Flaw Bypasses AT&T Samsung Galaxy S II Screen Lock
zacharye writes "BGR has uncovered a security flaw on AT&T's version of the Samsung Galaxy S II that renders Android's unlock pattern feature completely useless. Using a simple workaround, the security hole allows anyone to bypass the unlock pattern, which normally denies users access to an Android device unless a preset pattern is drawn on a grid of nine dots spread across the device's lock screen."
This is a common issue with lockscreen replacements. "WidgetLocker Lockscreen" on the android market calls it the "5 second rule". You have to wait about 5 seconds after turning your screen off to turn it back on again if you want the replacement lockscreen to show instead of the default one. I'm not sure why it's not a standard application request to replace the lockscreen, except that it could potentially be a security problem if any application could just decide to override another lockscreen.
This is why OEMs need to stop screwing with Android and just use the stock OS from Google.
I have an S2, and while the method described in TFA doesn't work on my S2 (maybe I'm just stupid, or maybe coz' mine isn't tied to AT&T, it's an unlocked one imported from elsewhere), I did notice if I look at the dark screen from an angle, my designated unlock pattern shows up clearly in the form of finger stain...
And when one is writing software it is hard to keep everything in order. Apple has made some bonehead mistakes. MS has made really silly mistakes. On thing that should be good for Android is that many eyes can be looking at the code, except when some firm believes security is easy and makes a bonehead mistake. It seems like this will happen more in phones like Android unlike Ms and Apple as firms have an incentive to make risky changes to interface to differentiate the phone, not to mention the need to sell phones cheap while paying MS major chunks of money in settlement.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
FTA: "If you have a PIN or an unlock pattern set, all you have to do in order to bypass it is simply tap the lock button to wake the display and then let the screen time out and go black. Tap the lock button again and low and behold, the unlock screen is gone and the phone can be accessed with no PIN or pattern input whatsoever."
I have the same phone, I noticed that by using the pattern lock, the finger can leave leave a fingerprint mark on the screen, from the skin oils, which one can easily follow as a blueprint to unlock the phone when the phone is turned to reflect light correctly.
I have had many friends try and use this technique to break into my phone, all of which succeeded even if the screen already had fingerprints on it.
I found that the issue is almost eliminated if the screen has a protector on it, since it is much harder to see the fingerprint marks.
Context. It's what's for breakfast.
There are two types of people in the world: Those who crave closure
I said it before and I will continue to say it:
Don't by branded phones.
I thought all phones had a brand, either by a carrier or by a manufacturer or both. And if by "branded" you meant "carrier-customized firmware", is there a way to buy a phone compatible with a non-AT&T U.S. carrier (that is, Verizon Wireless or Sprint) without buying it from the carrier?
Does anybody know if this affects the Bell Mobility devices in Canada? I know someone who owns one... wondering if I should bug them about it. Thanks.
Bow before me, for I am root.
But it isn't, all these things are intuitive and not hard to come up with yourself. Just because someone else thought of it before shouldn't mean you have to stop using your brain.
sort of: http://www.youtube.com/watch?v=ovfYBa1EHm4#t=90 Not that I adequately understand how either of these things occur, but I don't trust any system that I cannot disassemble, upgrade, and repair or modify myself. What I understand even less, is why people even use smart phones. Yeah, they can do all but warm your lunch (maybe soon) and disperse crowds, but between a laptop/desktop, and bare-bones phone, I just don't get it. ....Why do I feel like I just harmed a nun?
Laws are like sausages. It's better not to see them being made. - Otto von Bismarck
I've a GT-I9100 with the latest firmware and I can't reproduce it. Kinda odd. I wonder if its a AT&T version issue only, or if they have 3rd party software.
That being said, I'd never trust that stuff - specially the pattern - as a real security protection. It's easy to guess patterns, its easy to follow the finger's smudge (and you can guess even without that as patterns are not all that complex usually).
Bottom line its a protection against the jealous girlfriend, the little childrens, that sort of stuff. Default is to have no protection on the lock at all, which is just "drag to unlock", and thats the protection against accidental unlock only.
As programmer I am guessing it would just toggle back and forth till T+timeout.
So once T+timeout has elapsed, the phone could not be unlocked without a PIN. So lost phones have quite a short window of vulnerability. If what they say is true. I don't have a AT&T Samsung phone to test. My T-mobile branded LG Titanium always demands a PIN on wake up.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
"This is an important feature of the OS. It is designed to allow the malware fairy easy access to the phone so the user can quickly install harmful and annoying applications on the device. This way AT&T can keep up appearances as the dirty hooker of the mobile industry (Free and full of infections)."
Fixed that for you.
"Smarten up already, I don't want another 50 million zombied devices stealing credit card info or sending spam".
But Russia and China do.