The Reset Password add-on before 1.2.0 for Alfresco has a broken algorithm (involving an increment) that allows a malicious user to change any user's account password include the admin account.

Admin account takeover in Alfresco Reset Password

The Alfresco Reset Password add-on before version 1.2.0 relies on untrusted inputs in a security decision. Intruders can get admin's access to the system using the vulnerability in the project. Impacts all servers where this add-on is installed. The problem is fixed in version 1.2.0