Bytes over DNS, (Mon, Oct 27th)

I was intrigued when Johannes talked about malware that uses BASE64 over DNS to communicate. Take a DNS request like this: label1.label2.tld. Labels in a request like this can only be composed with letters (not case-sensitive), digits and a hyphen character (-). While BASE64 is encoded with letters (uppercase and lowercase), digits and special characters + and /. And also a special padding character: =.