This module will allow you to add Time-based One-time Password Algorithm (also called "Two Step Authentication" or "Multi-Factor Authentication") support to user logins. It works with Google's Authenticator app system and support most (if not all) OATH based HOTP/TOTP systems.

Accidental removal of account configuration

In certain scenarios, Google Authenticator login incorrectly determines the user's account name. The change in account name could cause the two-factor authentication for existing accounts to be lost, allowing users to log in using just username and password.

This vulnerability is mitigated by the fact while Google Authenticator login's additional verification is by-passed, a username and password are still required to log in.

One-time password (OTP) replay

If an attacker can intercept a login request with a username, password and OTP, an attacker could use this same data again to login to the website.

This vulnerability is mitigated by the fact that an attacker who can intercept a login request with this level of detail can usually also intercept the ongoing session identifying token.

CVE identifier(s) issued

  • Accidental removal of account configuration: CVE-2013-4177
  • One-time password (OTP) replay: CVE-2013-4178

Versions affected

  • Google Authenticator login 6.x-1.x versions prior to 6.x-1.2.
  • Google Authenticator login 7.x-1.x versions prior to 7.x-1.4.

Drupal core is not affected. If you do not use the contributed Google Authenticator login module, there is nothing you need to do.


Install the latest version:

Also see the Google Authenticator login project page.

Reported by

Fixed by

Coordinated by

Contact and More Information

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