CVE-2023-53978

myBB Forums 1.8.26 contains a stored cross-site scripting vulnerability in the forum announcement system that allows authenticated administrators to inject malicious scripts when creating announcements. Attackers can exploit this vulnerability by inserting script payloads in the announcement title field when adding announcements through the 'Forums and Posts' > 'Forum Announcements' interface, causing arbitrary JavaScript to execute when the announcement is displayed on the forum.