This seems to have been caused due to this commit:
http://git.savannah.gnu.org/cgit/emacs.git/commit/?h=emacs-25&id=0a21b26c58a241ac41cd12cd10cd605238bb2640

Relevant portion from the diff:

+    ;; Recognize the start of a bracketed paste sequence.  The handler
+    ;; internally recognizes the end.
+    (define-key map "\e[200~" [xterm-paste])

Copying Stefan as he authored that commit.
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-- 
Kaushal Modi