Azure AD High Number Of Failed Authentications For User
The following analytic identifies an Azure AD account experiencing more than 20 failed authentication attempts within a 10-minute window. This detection leverages Azure SignInLogs data, specifically monitoring for…
Description
The following analytic identifies an Azure AD account experiencing more than 20 failed authentication attempts within a 10-minute window. This detection leverages Azure SignInLogs data, specifically monitoring for error code 50126 and unsuccessful authentication attempts. This behavior is significant as it may indicate a brute force attack targeting the account. If confirmed malicious, an attacker could potentially gain unauthorized access, leading to data breaches or further exploitation within the environment. Security teams should adjust the threshold based on their specific environment to reduce false positives.
Detection logic
Detection requirements
- Platform
- ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteSaaSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- azure_active_directory
Known benign triggers
- A user with more than 20 failed authentication attempts in the span of 10 minutes may also be triggered by a broken application.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| attack.mitre.org/techniques/T1110/ | 8from 2 sources |
| attack.mitre.org/techniques/T1110/001/ | 5 |
From the source
- At source
- Open at source
- Upstream identifier
- 630b1694-210a-48ee-a450-6f79e7679f2c
- Tagged by the source as
- Azure Active Directory Account TakeoverCompromised User AccountAzure TenantcloudSplunk CloudSplunk EnterpriseSplunk Enterprise Securityidentity
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1