I had the same issue on Ubuntu 16.04 but found that apt wouldn't upgrade to the latest version of libnss3 by default.
I had to do the following:
- Open 'Software Updater', then click on 'settings' button
- Tick the 'important Security Updates (xenial-security) then close. it will update the cache
- Open terminal and then run the command 'sudo apt-get install libnss3'
Should then work