While Android devices running Android 5.0 Lollipop and later versions of the operating system are protected by full disk encryption like iPhones, those running Qualcomm processors are vulnerable as Qualcomm's security measures contain some flaws, and if any hacker exploits such flaws along with some flaws in Android, he can bypass the full disk encryption. In such a case, the hacker will be able to access your phone unless you choose to protect your privacy with a strong password.
Charge your phone at public charging stations? Your phone may get hacked
Gal Beniamini, the researcher who revealed such flaws, has been working both with Google and Qualcomm to fix them. While some of them have already been fixed, Beniamini believes that the entire hardware needs to be replaced to rid Android phones of flaws in full disk encryption.
There are other factors too that make Android phones vulnerable to hacking attempts which are turning stronger and more direct with the passage of time. One is that OEMs are notoriously slow in updating their devices with the latest Android operating systems and the other factor is that a majority of Android device users keep passwords which are easy to track and if you know a user, easy to guess.
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Back in January, security firm SplashData revealed that the most commonly used passwords of 2015 were ironically the easiest ones to guess. Among the top five most commonly used passwords, the firm identified '12345', '123456' and '12345678' which are basically sequences that anyone won't forget but hackers won't forget either. The firm also found popular and common terms like 'football', 'monkey' and 'starwars' in the list, despite the fact that websites and apps always recommend users to keep long, alphanumeric or hard to guess passwords and even rate them as per their complexities.
On the question of the vulnerability of smartphones, Kaspersky Labs recently published a report in which it claimed that charging your phone at public charging stations or unknown PCs may make it vulnerable to possible hacking attempts. As per the Kaspersky report, when smartphones are connected to public charging stations or PCs, they transmit data like 'device name, device manufacturer, device type, serial number, firmware information, operating system information, file system/file list, electronic chip ID.' The report adds that this set of information is enough for hackers to target your phone.