Open redirect Vulnerability

1 min readJan 27, 2020



There is an Open Redirect on due to the application not checking the value passed by the user to the “url” parameter.


Unchecked redirects occur when an application redirects to a destination controlled by attackers. This often occurs in functionality returning users to a previous page, e.g. after authenticating.

An attacker can control the value of the “url” parameter and make it redirect to a malicious endpoint.

Steps To Reproduce:

Here is a proof of concept to demonstrate how an open redirect occurs. Please note that this particular example is not a vulnerability and just here for demonstration purposes.


The URL looks like it should go to, but you are redirected to

Supporting Material/References:


When possible, do not allow user input to directly control redirect destinations; rather, generate them on the server side (e.g. via ID -> URL mapping). When this is not an option, a strict whitelist is highly recommended. Finally, a last-ditch mitigation can be performed by removing protocol specifiers from user input prior to redirection. This last method will not fix intra-site redirect exploits, but can prevent redirects to an attacker-controlled website.



Attackers may be able to use this to execute believable phishing attacks, bypass authentication, or (in rare circumstances) violate CSRF mitigations




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