A Study to Test How Zongertinib is Taken up in the Blood of People With and Without Liver Problems

This study is open to adults between 18 and 80 years of age. People with a body mass index (BMI) between 18 and 42 kg/m\^2 can take part. Women can only participate if they cannot get pregnant. This study includes people with mild liver problems, people with moderate liver problems, and people without liver problems as a matching control. The purpose of this study is to find out how mild and moderate liver problems affect how the body handles a medicine called zongertinib. Participants take zongertinib once as tablets. Participants with liver problems are treated in a step-by-step approach with a few days in between for the doctors to review the data and make sure the participants can tolerate the treatment. Participants may continue their regular treatment for their liver problems during the study. Participants are in the study for about 5 weeks. During this time, they visit the study site 4 times. This also includes an overnight stay for 6 nights. During study visits, the doctors regularly check participants' health and take note of any unwanted effects. To assess the study endpoints, the study staff regularly takes blood samples.