I used to be in the lab of a professor at a top 10 US university with an h-index of 90+ (essentially very well respected). I was working with a PhD student in the same group on a paper (the professor was not an author on this paper) and later found out I was not included in the authors list by the PhD student. I contacted the professor, who acknowledged that I should've been listed as an author but that it was too late to change at this point. I talked to other professors at the same institution who said that, realistically given who the professor is, it would be best not to poke the bear and doing so would likely not result in a positive outcome for me.
In this situation, how would I list this on my CV? It is a fairly significant work and thus I would like to list somehow. I can certainly answer questions in detail about any part of the work. However, I feel weird about listing a paper where I am not listed as an author.