We are having the same issue. Not sure we have all those security features in place. Certainly not hidden IP addresses. It happens when we mark all threads read
Code:
<a href="{vb:raw $vboptions.vbforum_url}{vb:if "$vboptions['vbforum_url']", '/', ''}forumdisplay.php?{vb:raw session.sessionurl}do=markread&f={vb:raw foruminfo.forumid}&markreadhash={vb:raw bbuserinfo.securitytoken}" rel="nofollow" onclick="return mark_forum_and_threads_read({vb:raw foruminfo.forumid});">
Can't use the modification from 3.8 Not sure what to do about this error... vB tech is stumped.
There was a fix for v.3.8 but doesn't seem to be relevant to v 4.
https://vborg.vbsupport.ru/showthrea...91#post2420691