There are way too many possible causes for this. For instance, it could be your system's Proxy settings, though if you're using Microsoft Windows then this would also likely affect MS IE. It may be good to see if Mozilla Firefox experiences the same issue, since Firefox has its own separate proxy settings.
An add-on could cause this. Resetting customized settings wouldn't be likely to "fix" this if the add-on is still installed. Removing add-ons might. Re-installing Chrome might.
If info is being inserted by an external device (e.g. from a hacked router, or incorrect DNS settings that cause your traffic to go through a MITM) then this would probably not be limited to Chrome.
Anti-Virus software may detect malware that is affecting things.
So I've now mentioned multiple different approaches to possibly fix this, because there are multiple possible causes. I expect that I haven't listed every possibility of what is causing this, but since there are so many things that could cause such an issue, we may need more details to figure out what's wrong (if the above steps don't help to more clearly identify the problem).