CVE Vulnerabilities

CVE-2021-39899

Weak Password Recovery Mechanism for Forgotten Password

Published: Oct 04, 2021 | Modified: Oct 12, 2021
CVSS 3.x
4.2
MEDIUM
Source:
NVD
CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
1.9 LOW
AV:L/AC:M/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

In all versions of GitLab CE/EE, an attacker with physical access to a user’s machine may brute force the user’s password via the change password function. There is a rate limit in place, but the attack may still be conducted by stealing the session id from the physical compromise of the account and splitting the attack over several IP addresses and passing in the compromised session value from these various locations.

Weakness

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

Affected Software

Name Vendor Start Version End Version
Gitlab Gitlab 1.0.0 (including) 14.1.7 (excluding)
Gitlab Gitlab 14.2 (including) 14.2.5 (excluding)
Gitlab Gitlab 14.3 (including) 14.3.1 (excluding)

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.

Potential Mitigations

References