1891628 - I have discovered an open redirect vulnerability in Firefox version 124.0 that allows malicious redirection of users to arbitrary websites.

Status: RESOLVED INVALID

(Firefox :: Security, defect)

Description

[salah eddine louffidi]

Attachment: redirection.png

Open Firefox browser (Version 124.0).
Enter the following URL in the address bar: https://example.com@dd.d.
Press Enter.
Note that the browser redirects to dd.d.
Affected URL:

Hostname: example.com
Subpage: N/A
Environment Details:

Firefox Version: 124.0
Operating System: All
Impact:
This vulnerability poses a significant risk to users as it can be exploited to redirect them to malicious websites without their knowledge, potentially leading to further exploitation or data theft.

Recommendation:
I recommend that the Firefox security team investigates and patches this vulnerability as soon as possible to protect users from potential exploitation.

Comment 1

[:Gijs (away/busy until Mar 10)]

Putting in [e-mail] is the same as trying to navigate to example.com with a foo username. So example.com@dd.d is like logging into dd.d with a example.com username. That is not a redirect, just direct navigation.

Comment 2

[salah eddine louffidi]

https://example.com@dd.d ==> not example.com@dd.d

so https://example.com==> is an url not an username

;)

Comment 3

[:Gijs (away/busy until Mar 10)]

(In reply to salah eddine louffidi from comment #2)

https://example.com@dd.d ==> not example.com@dd.d

so https://example.com==> is an url not an username

;)

That's really not how URL parsing works. Please see https://url.spec.whatwg.org/#authority-state .