Hello,
Is it possible that the warning from the title could derive from an SQL injection attempt?
These kind of warnings apeared from 5 oct 2017 on my mediawiki (1.23) log, but I didn't modified the files in any way.
Topic on Project:Support desk
1.23 is an ancient unsupported version which does not receive security upgrades anymore. Please upgrade to a supported version for your own safety.
You are right. But the upgrade process is so complex that I think a new installation is easier to do than an update......And after I finish the update a new version will be available... Anyway as long as that is an error it means that the hack did not succeed. Regards.