How I Found The open redirect vulnerability?

Hi everyone, i am back with another writeup. its simple

to find but where to look for this vulnerability is matter.

lets name it as https://:abc.example.com

it has login functionality. so i was tested login page

for other vulnerabilities like……

authentication bypass

OTP bypass

sql injection on login parameters

but no use its secure. Then i remembered my old writeup regarding

open redirect on 404 not found page and login page.

“https://medium.com/@doordiefordream/how-i-found-open-redirect-using-virus-total-460d721b9596”

so started testing, the login page url looks like:

https://abc.example.com/login

so i added open redirect parameter to above url

https://abc.example.com/login?returnTo=https://evil.com

then i was entered the login details and click on submit

boom,its redirected to evil.com.

then i was reported. its valid but i got duplicate ☹.

recent times i was getting more duplicates.

when i writing this writeup. my email alert me “you got another duplicate”

but its painful when we get duplicate…but still feel ☺ happy.