What are the .android folders and adbkey files on my computer?

Question

Today I discovered a folder in my home directory with the name .android.

Inside the folder are just two files, adbkey and adbkey.pub.

I have searched around and have found out that adbkey.pub is a Windows trojan. The files were last modified in January, but were just accessed a few hours ago. I have never used an Android device or Android SDK on my computer.

I have WINE installed on my computer. I also ran a ClamAV scan on the folder and it didn't detect anything.

Any ideas what this is and if I should be concerned?

Answer 1

If your computer has never had an Android device connected, then I don't know where those files came from.

On my computer (as I use both Android and its SDK) those files are an SSH key-pair that allow me to mark my computer as "trusted" to my phone.

SSH keys shouldn't be harmful.

If you want to verify that these are SSH keys, open ".android" in the file browser (Nautilus), right-click on "adbkey", and select Properties. The file's Type should be "PKCS#8 Personal Key in PEM format (application/pkcs8+pem)" and its Size exactly 1,704B. "adbkey.pub" should be a little over 700B.

("adbkey.pub" is unhelpfully described as a Microsoft Publisher file: I put this down to Nautilus making a guess from the extension; equally unhelpfully, the file command describes them both as "ASCII text".)

I can attach a sample copy of each file, if you want to confirm yours have the correct format.

Answer 2

Someone might have plugged their Android phone into one of your USB sockets. I have exactly the same folder on my Windows PC (for some reason it's on my Desktop), and that is the only reason I can think of it for it being there. I have a Samsung Android phone, and often plug it in to charge it and occasionally to transfer photos, videos, downloaded files etc. Why the folder is there, I don't know. I've deleted it.