CWE-640: Weak Password Recovery Mechanism for Forgotten Password

Description

The product contains a mechanism for users to recover or change their passwords without knowing the original password, but the mechanism is weak.

Submission Date :

Jan. 30, 2008, midnight

Modification Date :

2023-06-29 00:00:00+00:00

Organization :

Cigital
Extended Description

It is common for an application to have a mechanism that provides a means for a user to gain access to their account in the event they forget their password. Very often the password recovery mechanism is weak, which has the effect of making it more likely that it would be possible for a person other than the legitimate system user to gain access to that user's account. Weak password recovery schemes completely undermine a strong password authentication scheme.

This weakness may be that the security question is too easy to guess or find an answer to (e.g. because the question is too common, or the answers can be found using social media). Or there might be an implementation weakness in the password recovery mechanism code that may for instance trick the system into e-mailing the new password to an e-mail account other than that of the user. There might be no throttling done on the rate of password resets so that a legitimate user can be denied service by an attacker if an attacker tries to recover their password in a rapid succession. The system may send the original password to the user rather than generating a new temporary password. In summary, password recovery functionality, if not carefully designed and implemented can often become the system's weakest link that can be misused in a way that would allow an attacker to gain unauthorized access to the system.

Example Vulnerable Codes

Example - 1

A famous example of this type of weakness being exploited is the eBay attack. eBay always displays the user id of the highest bidder. In the final minutes of the auction, one of the bidders could try to log in as the highest bidder three times. After three incorrect log in attempts, eBay password throttling would kick in and lock out the highest bidder's account for some time. An attacker could then make their own bid and their victim would not have a chance to place the counter bid because they would be locked out. Thus an attacker could win the auction.

Related Weaknesses

This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined to give an overview of the different insight to similar items that may exist at higher and lower levels of abstraction.

Visit http://cwe.mitre.org/ for more details.