Mars Climate Orbiter, 1999: http://articles.latimes.com/1999/oct/01/news/mn-17288. Undetected metric conversion error (though unclear if this was a manual process or software).
Toyota unintended acceleration, 2010: https://www.edmunds.com/car-safety/for-toyota-owners-uninten.... Toyota maintains that it was not caused by software error.
Now let's list some cases where the software did have ultimate control:
Schiaparelli EDM lander, 2016: https://newatlas.com/esa-schiaparelli-mars-crash-inquiry/496.... Faulty decision-making in the automated descent system due to input saturation.
Tesla auto-pilot crash, 2016: https://www.theguardian.com/technology/2016/jun/30/tesla-aut.... Faulty decision-making due to incorrect image analysis. In this case, the additional safety controls (the driver himself) failed too.
Uber car crash, 2018: https://money.cnn.com/2018/03/20/news/companies/self-driving.... Faulty decision-making due to incorrect image analysis, though the investigation is still ongoing, so no definite cause determined (FAFAIK).
If you expect your doctor's software to be perfect, be prepared to pay for 2 software engineers salaries per doctor.
"AECL had never tested the Therac-25 with the combination of software and hardware until it was assembled at the hospital."
We on the other hand have the Therac-25.
We claim to be on a level of engineering fields. We should also act that way.