We were having the same problem and tried various fixes; restoring an older backup, editing the theme, disabling all plugins.
The cause of our issue was the social sharing plugin from addthis.com. Once we disabled it, all links on the site worked again.
Seems to be a few users here experiencing the same issue, so although I’m not sure if this’ll fix it for you guys, the above was the solution to our similar problem.
Good luck!
