I am studying about various block ciphers and their weaknesses, so I have a doubt about AES S-boxes, Is the difference distribution table of AES uniform ?
The difference distribution table for the AES s-box contains mostly probability 2/256 differentials. However, there is a single probability 4/256 for each input/output difference. I uploaded a dump of the table here so that you can see.
The code used to produce this table can be found here. Disclaimer: This is my personal github.
If by "uniform", you mean all values equal, the case is no. If you meant "differential uniformity", that is a term with a precise meaning:
From this paper, they define differential uniformity as "A mapping is called differentially uniform if for every non-zero input difference and any output difference the number of possible inputs has a uniform upper bound".
The AES s-box is a differential 4 uniform function
AES S-box DDT is not uniform but it has a higher resistant to differential attacks than DES because of maximum probablity of input output pair of differential is 4/256.