Use random number to check for code execution in werkzeug_debug_rce.rb

Co-authored-by: Julien Voisin <[email protected]>

Author: Grezzo

modules/exploits/multi/http/werkzeug_debug_rce.rb

@@ -298,7 +298,8 @@ def execute_python(cmd, secret, frame, cookies = '')
   end
 
   def check_code_exec(secret, frame, cookies = '')
-    execute_python(1, secret, frame, cookies).body.start_with? ">>> 1\n"
+    canary = rand()
+    execute_python(canary, secret, frame, cookies).body.start_with? ">>> #{canary}"
   end
 
   def check