Passing score on an individual exam is 5 out of 10.
If you pass all 5 of your exams, that's great.
If you pass only 4/5 of your exams, that's good enough so long as your advisor reports in Black Friday that your research is fine.
If you pass fewer than 4/5 of your exams, you must retake (only) those exams that you failed in an attempt to get to the 4/5 level. Exams are offered every January.
If you still don't get to the 4/5 level even after the retake, you may be terminated from the program in accordance with the rules that apply for students in the PhD Program for Computer Science.
The person who manages the exams is Lawrence Rapp (lrapp@andrew.cmu.edu). He can be contacted to get student scores and to schedule re-takes.