Please find attached word document which contains screenshots. 

Step 1: Access the URL and inject the xss payload in URL.

https://preprod-myXX.XXXXX.in/prweb/sso1/ex7EeZQhwqVsPcJXG37rCQ%5B%5B*/!STANDARD?IsLogin=true&SelTab=ExistingUser&pzPostData=-271446842

Step 2: Injecting javascript code in the url.

Result: javascript code is seen resulting in a pop up showing xss vulnerability

Thanks,