Yes, this is a bug. The result shape is definitely wrong, regardless check shape gives no errors on it.
You are welcome to report this bug in the bug tracker.
Archived discussion
BRepAlgoAPI_Fuse bug
I have tow boxes like the Attachments（two box.BRep）,
When I used BRepAlgoAPI_Fuse with those boxes，
The result was wrong （wrong result.png）
Discussion
1 archived reply
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