Can android leak?

[mnamktmi 0]

I know Windows requires a properly configured firewall to prevent DNS leaks so I'm wondering if android has a similar vulnerability. I would assume it does but I haven't seen any mention of it. If so is there there anything that can be done to prevent it? Firewall?

[S.O.A. 82]

On my android devices I have no such leaks. You should be good to go!

[InactiveUser 185]

On a rooted device, you should check out the excellent open source iptables frontend AFWall+:

 

https://f-droid.org/repository/browse/?fdid=dev.ukanth.ufirewall

 

In its preferences, enable "VPN control" to give you fine-grained control over every app's connectivity (allow app traffic via: WiFi / Mobile Data / only via VPN / none).

 

Another interesting setting to consider would be "Fix Data Startup Leak" which prevents Android from sending any packets before AFWall's iptables rules are loaded. Be careful with this option, it's incompatible with certain devices, preventing them from booting. It's happened to me with several devices so I leave this option disabled. As a workaround (which may or may not be effective), I put my devices in airplane mode prior to rebooting.