My 'gut' intuition is that doing that is the same as applying the cipher of length 2, then the cipher of length 3, 5, 7 each in turn invidually, but I haven't h

My 'gut' intuition is that doing that is the same as applying the cipher of length 2, then the cipher of length 3, 5, 7 each in turn invidually, but I haven't had the chance to dig out cyberchef to confirm this. Edit: Indeed: (no spoilers for the fun of actually breaking your message) https://gchq.github.io/CyberChef/#recipe=Vigen%C3%A8re_Encode('WI')Vigen%C3%A8re_Encode('LHE')Vigen%C3%A8re_Encode('LMVON')Vigen%C3%A8re_Encode('HACKENS')&input=QUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEKQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEKQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUEgQUFBQUE https://gchq.github.io/CyberChef/#recipe=Vigen%C3%A8re_Encod...