The cuke in your hand looks much more like inconsistent water issues than any fungus. Plus the leaves in the photo look normal. Fungus issues will most often show up on the leaves, the plant itself, and seldom on the fruit.

But inconsistent water issues leads to not only bitterness but scarring and cracking on the fruit skins, shriveling (as at the top) and the development of white patches. Cukes are very water dependent plants and the consistency of that soil moisture level is quite important to them.

Dave

Thank you so much for the reply. I live in South Texas and we just went thru hurricane Harvey so I'm wondering how much of an effect that had on it added with the heat here.

Very possible. Plus if you had the hard pounding rains or any hail some of that exterior damage may be from that.

Dave