Adversaries may interrupt availability of system and network resources by inhibiting access to accounts utilized by legitimate users. Accounts may be deleted, locked, or manipulated (ex: changed credentials) to remove access to accounts. Adversaries may also subsequently log off and/or perform a System Shutdown/Reboot to set malicious changes into place.[1][2]
In Windows, Net utility, Set-LocalUser and Set-ADAccountPassword PowerShell cmdlets may be used by adversaries to modify user accounts. In Linux, the passwd utility may be used to change passwords. Accounts could also be disabled by Group Policy.
Adversaries who use ransomware may first perform this and other Impact behaviors, such as Data Destruction and Defacement, before completing the Data Encrypted for Impact objective.
| ID | Name | Description |
|---|---|---|
| S0372 | LockerGoga |
LockerGoga has been observed changing account passwords and logging off current users.[1][2] |
| S0576 | MegaCortex |
MegaCortex has changed user account passwords and logged users off the system.[3] |
| S0688 | Meteor |
Meteor has the ability to change the password of local users on compromised hosts and can log off users.[4] |
This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.
| ID | Data Source | Data Component |
|---|---|---|
| DS0026 | Active Directory | Active Directory Object Modification |
| DS0002 | User Account | User Account Deletion |
| User Account Modification |
Use process monitoring to monitor the execution and command line parameters of binaries involved in deleting accounts or changing passwords, such as use of Net. Windows event logs may also designate activity associated with an adversary's attempt to remove access to an account:
Alerting on Net and these Event IDs may generate a high degree of false positives, so compare against baseline knowledge for how systems are typically used and correlate modification events with other indications of malicious activity where possible.