How Redirects work on Facebook? Technical breakdown

Recently I was been working on Facebook Whitehat program and I wanted to explain a bug which I found — OPEN REDIRECT

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Hey, hope all are good. I’m Abhisek here

Disclaimer: This is for educational purposes only. I’m not in any way liable for any misuse.

When I was looking for low hanging bugs on Facebook, open redirect was the one which attracted me. So quickly launched Facebook and looked the requests sent during the process of redirection.

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Request No-32, caught my eyes on Open redirection bug. Took the request URL and tried to change the destination from

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Changes in the Request URL

You know what? Request succeeded and I was able to redirect from Facebook domain!!!!!

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MEME [WOW VERY NICE]

But wait what does Facebook Whitehat program says? Request to https://evilzone.org is only been accepted as open redirect. So tried to redirect to Evilzone site, but Facebook security Linkshim detected it was malicious and request did not pass.

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MEME [UNLUCKY]

Tried to bypass in different ways, Some of them are domain.evilzone.org, Domainevilzone.org, domain.org.evilzone.org, but none of them succeeded. Then I left this bug and worked on some other but I was unlucky. After some time link shortening caught my attention, as expected the redirect worked.

Again unlucky, Then after a long time. A small idea sparked on my head,

Why don’t I redirect using IP address? YES you know, I was able to redirect without any errors or defense. Finally Again reported!

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After this response, Me

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However it maybe, Consistency is very important in Bug Bounty and Cyber Security Field.

Byee, Hope you had a good read!

Written by

Cyber Security Researcher, Love your passion HACKING :)

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