Adversaries may stop or disable services on a system to render those services unavailable to legitimate users. Stopping critical services can inhibit or stop response to an incident or aid in the adversary's overall objectives to cause damage to the environment.
Adversaries may accomplish this by disabling individual services of high importance to an organization, such as
MSExchangeIS, which will make Exchange content inaccessible . In some cases, adversaries may stop or disable many or all services to render systems unusable. Services may not allow for modification of their data stores while running. Adversaries may stop services in order to conduct Data Destruction or Data Encrypted for Impact on the data stores of services like Exchange and SQL Server.
Operate intrusion detection, analysis, and response systems on a separate network from the production environment to lessen the chances that an adversary can see and interfere with critical response functions.
|Restrict File and Directory Permissions||
Ensure proper process and file permissions are in place to inhibit adversaries from disabling or interfering with critical services.
|Restrict Registry Permissions||
Ensure proper registry permissions are in place to inhibit adversaries from disabling or interfering with critical services.
|User Account Management||
Limit privileges of user accounts and groups so that only authorized administrators can interact with service changes and service configurations.
Monitor processes and command-line arguments to see if critical processes are terminated or stop running.
Monitor for edits for modifications to services and startup programs that correspond to services of high importance. Look for changes to services that do not correlate with known software, patch cycles, etc. Windows service information is stored in the Registry at
HKLM\SYSTEM\CurrentControlSet\Services. Systemd service unit files are stored within the /etc/systemd/system, /usr/lib/systemd/system/, and /home/.config/systemd/user/ directories, as well as associated symbolic links.
Alterations to the service binary path or the service startup type changed to disabled may be suspicious.
Remote access tools with built-in features may interact directly with the Windows API to perform these functions outside of typical system utilities. For example,
ChangeServiceConfigW may be used by an adversary to prevent services from starting.
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