Avira USSD Exploit Blocker
This app protects you from the dirty USSD hack, which could erase your SIM card or even execute a factory reset if you visit a malicious web page, either through a bad link or QR code. Any smartphone running Android 4.1 or earlier may be vulnerable to an unwanted USSD wipe.
How it works
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When you click on a web link or scan a QR code, Android will open a dialog with a list of apps that you can choose from to complete the action. Select ‘Avira USSD Exploit Blocker’ and set it as the default.
Protecting your phone from the USSD Android exploit is that simple!
What is a USSD code anyway?
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USSD codes are keypad commands that can be used to access a variety of phone functions, from checking minutes to accessing expert controls. USSD commands typically contain a mixture of numbers, stars and pound signs.