Windows Set Account Password Policy To Unlimited Via Net
Description
The following analytic detects the use of net.exe or net1.exe to configure the Windows maximum password age policy as unlimited.
It leverages process creation telemetry from Endpoint Detection and Response (EDR) agents and identifies executions of the net accounts command using the /maxpwage:unlimited option.
When specified, Windows configures the maximum password age with an unlimited value, effectively preventing passwords governed by the affected password policy from expiring.
This behavior is significant because an adversary may modify password expiration settings to weaken credential security controls and maintain access to compromised accounts for an extended period.
If confirmed malicious, this activity may indicate an attempt to establish or maintain persistence by preventing expected password rotation from invalidating credentials under the affected password policy.
Query · spl
| tstats `security_content_summariesonly`
values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime
FROM datamodel=Endpoint.Processes WHERE
`process_net`
Processes.process="* accounts *"
Processes.process IN ("* /maxpwage:unlimited*")
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_set_account_password_policy_to_unlimited_via_net_filter`
Implementation guide
The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
Known false positives
- This behavior is not commonly seen in production environment and not advisable, investigate the activity and determine if it is malicious. Apply additional filters to reduce false positives as needed.
Analyst notes
Known false positives: This behavior is not commonly seen in production environment and not advisable, investigate the activity and determine if it is malicious. Apply additional filters to reduce false positives as needed.