Android is a generally secure OS, although it occasionally falls victim to being open-source. That’s the problem with giving people the keys to the kingdom. Sometimes they do things that they don’t like. This is one of those things. One of the good folks on XDA has figured out a way to break through a pattern lock via some creative hacking.
Before we get into this, we must ask that you use this information responsibly. This is only for people who have locked themselves out of their phone and need to get back in. Do not use this to break into other people’s phones. With that out of the way, here’s how to hack the pattern lock.
First, this requires a working copy of Android Development Bridge, or ADB. ADB is a set of command-line tools released by Google for developers. We’d recommend getting it regardless of whether you do this hack, as it’s useful for all sorts of hacks.
Next, reboot into recovery and make a nandroid backup. This hack involves changing some root settings. A nandroid will make it easy to reset everything once you’re done.
Now open the Settings app and go to Developer options. Turn on USB debugging and enable root access for apps and ADB.
If your phone does not already have a pattern lock, enable one in Settings. Now lock the phone.
Command Line Tools
Now, open up Command Prompt. On Windows, click the Start button and type “cmd” and press enter. This will open the command line. Type the following commands in, pressing enter after each line:
update system set value=0 where name=’lock_pattern_autolock';
update system set value=0 where name=’lockscreen.lockedoutpermanently';
Reboot the phone and begin entering the second command:
adb shell rm /data/system/gesture.key
Reboot one more time. Any pattern should unlock the phone. It worked for us on Jelly Bean and has been confirmed to work on Gingerbread and Ice Cream Sandwich.
Protection Against This Hack
Thankfully, there are a few ways to protect yourself from this hack being used to break into your phone. First and most importantly, turn off USB debugging. Next, set root access to apps only. These two safeguards should block intruders.
Once again, we at TechNorms would like to remind you that this hack is meant to be used responsibly. Do not under any circumstances use this inappropriately. You know what they say about great power and great responsibility.
You may check out the original thread for any doubts or questions.