Try the following hopefully it will rid your mac of viperdns.
Go to System Preferences ~> Network,
In the top menu select Location and then "Edit Locations"
Use the (-) to delete the current location & use the (+) to add a new location,
Try connecting to the internet & see if the problem is still present.
If so, try completely resetting your Network connections. Navigate to:
Macintosh HD ~> Library ~> Preferences
Drag the ‘SystemConfiguration’ folder to the Trash BUT NO NOT EMPTY THE TRASH.
Now Restart your computer.
Your Mac will create new ‘SystemConfiguration’. When you log back in your Network and Bluetooth connections will be reset. Try connecting to the internet to test if the problem has gone.
If not you can replace the ‘SystemConfiguration’ folder with original folder currently in the Trash if you wish to reinstate your previous Network Settings.
