For background there is https://nickler.ninja/blog/2016/12/17/a-problem-with-ringct/ and this problem had been fixed before this post was made by changing ASNL to borromean signature. For background on what borromean signature is here is this question for background on what borromean signatures are What are Borromean signatures?What are Borromean signatures? Now obviously it has already been fixed but what was the exact problem with ASNL that could have been exploited in more simple terms?