Trac spam.
Someone out there has developed a crawler that attacks Trac wiki pages. Once it’s found a Trac installation, it posts an update to the WikiStart
and TracIni
pages. The new version appends a number of links, hidden from view using Trac’s syntax to allow arbitrary HTML:
{{{ #!html <u style="display:none"> ...nasty links... </u> }}}
I’ve been hit over at the FeedTree trac a few times; it’s infrequent enough that periodic checking of the timeline view is sufficient to spot and clean out the crud.
(I guess you know your software has “made it” when someone else writes a piece of software specifically to attack it.)