Excessive user account lockouts

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	1 Hour
Deduplication Period	1 Day
Required Data	Requires one of the following data sources: Windows Event Collector OR XDR Agent with eXtended Threat Hunting (XTH)
Detection Modules	Identity Analytics
ATT&CK Tactic	Credential Access (TA0006)
ATT&CK Technique	Brute Force (T1110), Brute Force: Password Spraying (T1110.003)
Severity	Low

Description

A high amount of user accounts were locked out from a single source host in a short time period. This may be the result of a brute-force or password spray attack.

Attacker's Goals

An attacker may be attempting to gain unauthorized access to user accounts.

Investigative actions

• Investigate the associated authentication attempts and login failures (e.g. 4740, 4625, 4776 events).
• Determine if any programs have stored outdated credentials, causing account lockouts.
• Find the computer responsible for the lockouts and verify if it exists on the domain.
• Monitor services that may be running with a user's credentials.

Variations

Excessive user account lockouts from a suspicious source

Synopsis

Field	Value
ATT&CK Tactic	Credential Access (TA0006)
ATT&CK Technique	Brute Force (T1110), Brute Force: Password Spraying (T1110.003)
Severity	Medium

Description

A high amount of user accounts were locked out from a single source host in a short time period. This may be the result of a brute-force or password spray attack.

Attacker's Goals

An attacker may be attempting to gain unauthorized access to user accounts.

Investigative actions

• Investigate the associated authentication attempts and login failures (e.g. 4740, 4625, 4776 events).
• Determine if any programs have stored outdated credentials, causing account lockouts.
• Find the computer responsible for the lockouts and verify if it exists on the domain.
• Monitor services that may be running with a user's credentials.

Excessive account lockouts on suspicious users

Synopsis

Field	Value
ATT&CK Tactic	Credential Access (TA0006)
ATT&CK Technique	Brute Force (T1110), Brute Force: Password Spraying (T1110.003)
Severity	Medium

Description

A high amount of user accounts were locked out from a single source host in a short time period. This may be the result of a brute-force or password spray attack.

Attacker's Goals

An attacker may be attempting to gain unauthorized access to user accounts.

Investigative actions

• Investigate the associated authentication attempts and login failures (e.g. 4740, 4625, 4776 events).
• Determine if any programs have stored outdated credentials, causing account lockouts.
• Find the computer responsible for the lockouts and verify if it exists on the domain.
• Monitor services that may be running with a user's credentials.