Potential MFA Bypass Using Legacy Client Authentication
Detects successful authentication attempts originating from clients using legacy authentication methods, identifiable via specific user agent strings. This activity can indicate an adversary attempting to bypass multi-factor authentication (MFA), potentially as part of a password spray attack. Legacy authentication protocols often do not support modern MFA mechanisms, making them a target for attackers who have obtained valid credentials through other means or are performing brute-force attacks like password spraying.
Sigma
