I've been working on a site for over a year and just now notice Redux Framework is somehow on the site. Noticed it when I went to Tools > Backup and saw it was in Tools. Clicked on it and saw the whole What's New page along with other tabs talking about it. I have been the only person to install anything or to upgrade in at least 6 months. Site owner confirms this.
Went to plugins to see Redux Framework and don't see it installed. Checked my theme's function file and don't see it being called up.
The same theme has been in effect for at least 6 months (I switched it out to do troubleshooting only).
How do I locate where this is? And does the existence of this framework mean that the site has been hacked somehow?