Azure Unusual Authentication Interruption
This rule detects unusual authentication interruptions in Azure Active Directory sign-in logs. Specifically, it looks for three types of ResultType and ResultDescription combinations: '50097 - Device authentication is required', '50155 - DeviceAuthenticationFailed', and '50158 - ExternalSecurityChallenge - External security challenge was not satisfied'. These events indicate that an authentication attempt was interrupted or failed due to device-related issues or an unmet external security challenge, which could be indicative of an adversary attempting to bypass authentication mechanisms or encountering unexpected security controls.
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