The past few weeks I've been seeing more and more of these probes each day. I'd like to figure out what vulnerability they're looking for but haven't been able to turn anything up with a web search.

Here's a sample of what I get in my morning Logwatch emails:

A total of XX possible successful probes were detected (the following URLs contain strings that match one or more of a listing of strings that indicate a possible exploit):

/MyBlog/?option=com_myblog&Itemid=12&task=../../../../../../../../../../../../../../../proc/self/environ%00 HTTP Response 200
/index2.php?option=com_myblog&item=12&task=../../../../../../../../../../../../../../../../proc/self/environ%00 HTTP Response 200
/?option=com_myblog&Itemid=12&task=../../../../../../../../../../../../../../../proc/self/environ%00 HTTP Response 301
/index2.php?option=com_myblog&item=12&task=../../../../../../../../../../../../../../../proc/self/environ%00 HTTP Response 200
//index2.php?option=com_myblog&Itemid=1&task=../../../../../../../../../../../../../../../proc/self/environ%00 HTTP Response 200

This is coming from a current CentOS 5.4 / Apache 2 box with all updates.

I've manually tried entering a few in to see what they get, but those all appear to just return the site's home page. This server is just hosting a few Joomla! sites... but this doesn't seem to be targeting Joomla (as far as I can tell).

Anyone know what they're probing for? I just want to make sure whatever it is I've got it covered (or not installed). The escalation of these entries has me a bit concerned.