Case "CV" steel is an alloy steel, non-stainless. It is not carbon steel, as it has small additions of Chromium and Vanadium, whence the name "CV". These additions to the alloy give improved properties to the steel. Those improved properties include finer grain size and improved uniformity in tempering. As a user, the finer grain size leads to the capability to take a very fine edge.
Case has never revealed the composition of CV steel. Based on edge retention testing I have performed, I do not think it is modified 1095, as it was out-performed by Buck 420HC in manila rope cutting. I suspect it is modified 1085 or 1075, but only Case knows for sure.
I find the Case CV steel takes a VERY fine edge with minimal effort. I also find that it holds an edge better than Case Tru-Sharp, though not as well as Buck 420HC.
For an EDC steel, it is excellent.