Steps to reproduce the issue

in com_redirect /administrator/index.php?option=com_redirect create a new Redirect Link with

Expired URL = "123"
New URL = "123"

Click SAVE, correctly note that there is an error : "Save failed with the following error: The source and destination URLs can't be the same."

Change to be

Expired URL = "123"
New URL = "AAA"

Click SAVE & Close, note item is saved correctly ✅

Select the check box next to the item

Click Batch Update Selected URL(s) button

Type

New URL = "123"

Click update links - congratulation the link was updated with invalid data because now the link is:

Expired URL = "123"
New URL = "123"

which is against the validation rules.

Expected result

Validation should kick in while batch updating links

Actual result

Insufficient validation of input before making changes to the database.