One of the many B-17s used in the German Air Force.
That may be an illustration of a B-17 with Luftwafte markings, but unless you post a photo, your caption is incorrect. I’m not saying that they didn’t use B-17s, I know they did, but you shouldn’t use that caption with a drawing, it’s totally out of context.
I have to agree with "ole" Hos Bandit on this one. Someone has just dragged and dropped some German markings. If the Germans had any B-17s they would have been captured, possibly forced down but certainly not purchased from Boeing.
This link will take you the story of the Germans using B-17s. Yes they used captured and repaired B-17s. After America and England the Germans flew the most B-S at one time during the war.