Missing authorization in the kitty drag and drop protocol allows a client to obtain dragged file contents without a drop

Missing Authorization in the drop handling path of the drag and drop protocol in kitty from 0.47.0 before 0.49.0 allows a program writing to the terminal to obtain the contents of files dragged over the window even when the user never completes the drop, because drop_enqueue_request() in kitty/dnd.c serves a drag data request without first checking the drop state of the window, so a client that issues the request while a drag is merely hovering receives the data offered for the drag. In the same file, drop_left_child(), which runs when the drag leaves the window without a drop having occurred, releases the offered MIME list but retains the pending request state, the open file descriptor and its main loop transfer timer, the directory handles, the URI list and the pending MIME name, so a client can continue to read through a retained directory handle, and an in-flight file transfer continues to stream, when no drag is in progress. The file contents are read from the filesystem by the kitty process itself using the paths the drag source offered. This results in disclosure of the contents of files the user moved over the window without ever releasing them into it.