The failure presents as a camera problem rather than a lens problem: with the lens attached, the body may become inoperable, or the rear monitor may misbehave. Sony identified the cause as the failure of a specific electrical printed circuit board within the lens.
Sony noted that only the symptom caused by that board qualified for free repair, and that failures caused by other components could carry a cost.
This is a case worth understanding structurally. An owner experiencing it would reasonably assume their camera body had failed, and would report it that way. Reliability data that does not capture which lens was mounted at the time will attribute this fault to the wrong product indefinitely.