UnrealIRCd < 3.2.10.7 and 4.x < 4.0.6 - Authentication Bypass via SASL AUTHENTICATE Parameter
The m_authenticate function in modules/m_sasl.c in UnrealIRCd before 3.2.10.7 and 4.x before 4.0.6 allows remote attackers to spoof certificate fingerprints and consequently log in as another user via a crafted AUTHENTICATE parameter.