The factory reset function in Android is supposed to be a practical and quick way of wiping an Android device once users decide to sell it or pass it on, but according to Avast’s research it is not bulletproof. 

Avast researchers purchased 20 used Android phone on eBay and started tinkering with them in an effort to restore the wiped information. Avast says the process involved “simple and easily available” software, which means it well within the reach of mere mortals who do not have the same resources as a security outfit.

Eventually Avast managed to recover more than 40,000 stored photos, including 1,500 family photos of children, more than 750 photos of women in “various stages of undress” and more than 250 photos of the previous owners’ manhood. Avast describes the latter as ‘selfies’ and this raises additional questions, mostly those involving personal hygiene rather than tech.

However, it is not as bad as it sounds. Avast managed to establish the identity of four previous owners. It also got 250 contact names and email addresses and one completed loan application. It seems the really important stuff is a lot more secure than photos.

There is no word on mobile banking apps or digital wallets, but since they are not mentioned in the report, it is safe to assume they were not compromised.

Avast says the only way of completely deleting all data from your Android device prior to selling it is to overwrite everything. Coincidentally Avast has an app that does it for you, which explains why it bothered looking at all those used phones and manhood selfies in the first place.