From the FluentValidation documentation I learned that I can abort validation by setting the cascade mode.
RuleFor(x => x.Surname) .Cascade(CascadeMode.StopOn
You can set CascadeMode at the global level by setting
ValidatorOptions.CascadeMode = CascadeMode.StopOnFirstFailure;
or at property level by
RuleFor(x => x.PropertyName) .Cascade(CascadeMode.StopOnFirstFailure)