Vandal

Vandalism is any addition, removal, or change of content, in a deliberate attempt to compromise the integrity of a wiki.

Examples

"Very nice site!" vandal

Nemo bis writes, "This is an extremely common comment spam pattern on blogs (perhaps even the most common nowadays). Usually they include a link to their website, I don't know if for clicking or for pagerank. It's possible that there is no specific aim for mediawiki and they're just posting the same stuff everywhere (failing to post an URL because there is no "website" field for "comments" in MediaWiki)."