CVE 2016-6336

MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote authenticated users with undelete permissions to bypass intended suppressrevision and deleterevision restrictions and remove the revision deletion status of arbitrary file revisions by using Special:Undelete.

See the CVE page on Mitre.org for more details.