Has anyone faced this issue and how have you resolved it? • have a backend service deployed as LB in k8s • trying to hit the end point from client web app. We get CORS issues. • But if we deploy the same as separate ingress we don’t get the CORS issues on client Is it K8 LBs overwrite the headers? or am i missing something here?

K8s doesn't have any lb implementation. It depends on your vendor. You can check headers of both responses and compare.