Drupal's uniqueness checking for certain user fields is inconsistent depending on the database engine and its collation.
As a result, a user may be able to register with the same email address as another user.
This may lead to data integrity issues.
Install the latest version:
- If you are using Drupal 10.2, update to Drupal 10.2.11.
- If you are using Drupal 10.3, update to Drupal 10.3.9.
- If you are using Drupal 11.0, update to Drupal 11.0.8.
- Drupal 7 is not affected.
All versions of Drupal 10 prior to 10.2 are end-of-life and do not receive security coverage. (Drupal 8 and Drupal 9 have both reached end-of-life.)
Updating Drupal will not solve potential issues with existing accounts affected by this bug. See Fixing emails that vary only by case for additional guidance.
- Wayne Eaker
- cilefen of the Drupal Security Team
- Kristiaan Van den Eynde
- Drew Webber of the Drupal Security Team
- Lee Rowlands of the Drupal Security Team
- Juraj Nemec of the Drupal Security Team
- Benji Fisher of the Drupal Security Team
- xjm of the Drupal Security Team