[dotbill]

Challenge Five is here:

http://www.standard.co.uk/advertorials/gchq/

[atanasb]

What are the answers for 3 and 4? I seem to be stuck.

[dotbill]

I found that page through other means.. ok.. now onto 3 and can't solve it!

[benmmurphy]

first look at the 3rd one the ciphertext looks consistent with random data at least for single byte frequencies.

[gazza126]

figured out 3rd one yet??