Monday, January 7, 2013

Facebook Bug #4: Password Reset Vulnerability Found in www.facebook.com

Description
Sow Ching Shiong, an independent vulnerability researcher has discovered a Password Reset vulnerability in www.facebook.com, which can be exploited by an attacker to bypass certain security restrictions.

In normal circumstances, an authenticated Facebook user is required to enter his/her current password on the change password page to prevent an unauthorized person from changing the password without the user's knowledge.

However, an attacker can change/reset a user's password without knowing the user's current password by accessing this URL directly: https://www.facebook.com/hacked.
After that, the page will be redirected to https://www.facebook.com/checkpoint/checkpointme?f=[userid]&r=web_hacked
Now, the attacker can click "Continue" to change/reset the user's password.

Proof of concept
Step 1: Logon to Facebook and access this URL directly: https://www.facebook.com/hacked. The page will be redirected to https://www.facebook.com/checkpoint/checkpointme?f=[userid]&r=web_hacked


Step 2: Click on "Continue" to proceed


Step 3: Enter "New Password" and "Confirm Password" to change/reset the password.


Conclusion
This vulnerability has been confirmed and patched by Facebook Security Team. I would like to thank them for their quick response to my report.

Facebook White Hat

https://www.facebook.com/whitehat