CVE-2017-8812
MediaWiki before 1.27.4, 1.28.x before 1.28.3, and 1.29.x before 1.29.2 allows remote attackers to inject > (greater than) characters via the id attribute of a headline.
Date published : 2017-11-15
https://lists.wikimedia.org/pipermail/mediawiki-announce/2017-November/000216.html