I had this error pop up on 2 pages this morning, within the last 48 hours have installed three new plugin… Ultimate security, Bad query blocker and duplicator & the standard myriad of hand coded security necessary for a adequate install hardening. {htcaccess, hiding files, header mods}.
I had recently had to nuke another security plugin install manually from my directory as it conflicted with plugins.
I did not turn up a search result for the strings. I did run across a post on stackoverflow which curiously enough popped up with in the last 36 hours of this event. here .
Perhaps a code update witha shared plugin is conflicting?
Changing the template applied within the page attribute that I had applied to the page made the error disappear, but as sneedderek implied I definitely get a malware return from the scan link he provided. Further findings welcome…