Specifically, the file is: /usr/local/www/data-dist/technoforum.de/public_html/ubb/cache-AS88CL86/search_index/forum28_recentmeta.cgi

But I'd recommend purging the entire folder and rebuilding.

And as sugguested, an upgrade is highly advised as it would allow users to remotely execute their code on your server which could do any number of nasty irrecoverable things (to your site or the entire server depending on security).

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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