SEP sesam before 5.2.0.24 mishandles User Authorization with MFA.

Summary

SEP sesam before 5.2.0.24 mishandles User Authorization with MFA. If AD authentication is configured and MFA is enforced, an attacker can create a second OTP access capability. SEP sesam and Active Directory handle username capitalization differently, which may allow multiple SEP sesam user accounts to be created for the same Active Directory (AD) account. Active Directory treats usernames as case-insensitive, while SEP sesam distinguishes between different letter casing. As a result, the same AD user can be represented by multiple SEP sesam user accounts that differ only in username capitalization. When Active Directory authentication is configured and multi-factor authentication (MFA) is enforced, this behavior may allow an additional OTP Authenticator to be registered for the same AD account, reducing the effectiveness of MFA protection.