--- mysql-dump-hashes.nse	2015-11-05 15:41:05.000000000 -0500
+++ mysql-dump-hashes-fixed.nse	2018-08-19 14:47:49.877692000 -0400
@@ -84,12 +84,24 @@
 
     local status, response = mysqlLogin(socket, username, password)
     if ( status ) then
-      local query = "SELECT DISTINCT CONCAT(user, ':', password) FROM mysql.user WHERE password <> ''"
+      local query = "SELECT DISTINCT CONCAT(user, ':', password) "..
+                    "FROM mysql.user WHERE password <> ''"
       local status, rows = mysql.sqlQuery( socket, query )
-      socket:close()
       if ( status ) then
         result = mysql.formatResultset(rows, { noheaders = true })
+        socket:close()
         break
+      else
+        -- From MySQL version 5.7 on the authentication_string column is used
+        local query = "SELECT DISTINCT CONCAT(user, ':', authentication_string) "..
+            "FROM mysql.user "..
+            "WHERE authentication_string <> '*THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE'"
+        local status, rows = mysql.sqlQuery( socket, query )
+        socket:close()
+        if ( status ) then
+          result = mysql.formatResultset(rows, { noheaders = true })
+          break
+        end
       end
     else
       socket:close()