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Account disabled, deleted or reset from a command line

AN0334 asks for user account modification — reset, disable or deletion — correlated with the process lineage that performed it, and this rule takes the process-creation half of that pairing: the shipped tools that carry out the change, each anchored on the flag or verb that makes it destructive rather than a read. The `net.exe` legs require both ` user ` and either `delete` or `active:no` on the same command line, `net1.exe` is listed alongside because `net.exe` hands most subcommands to it, and the cmdlet legs name the local-account and directory forms that disable, remove or reset an account. Three limits worth stating. A cmdlet typed into a PowerShell session that is already running creates no process and is invisible here; the brief's other log source, Security 4723/4724/4740, records the account change itself and would see it, but it is a different logsource and this rule does not use it. The bare `net user <name> <password>` form has no flag to anchor on and is not selected. And Sigma models no aggregation, so a single service-desk reset and a sweep that resets every account in the domain — the LockerGoga behaviour this technique is named for — produce identical single events here, which is why the level sits at the bottom of the scale. MITRE's UserContext, TimeWindow and ParentProcessName knobs all need a baseline or a time window that Sigma cannot express, so none of them is encoded. The brief's process-creation source for this analytic is Sysmon EventID 1; confirm process creation is not filtered out of the running Sysmon config before reading an empty result as quiet rather than blind. UNVERIFIED AS AUTHORED — derived from MITRE ATT&CK DET0120, not hand-written and not tested by its author. Any lab result is on this rule's own page.Full description

The detection

The 4 SIEM queries below are previews produced by Siemphony’s own translator, not pySigma, and none has been executed against a real backend — review before you deploy.

detection.yml

title: Account disabled, deleted or reset from a command lineid: be885340-a516-4e4e-a968-d5bcf0cba502status: experimentaldescription: |  AN0334 asks for user account modification — reset, disable or deletion —  correlated with the process lineage that performed it, and this rule takes  the process-creation half of that pairing: the shipped tools that carry out  the change, each anchored on the flag or verb that makes it destructive  rather than a read. The `net.exe` legs require both ` user ` and either  `delete` or `active:no` on the same command line, `net1.exe` is listed  alongside because `net.exe` hands most subcommands to it, and the cmdlet legs  name the local-account and directory forms that disable, remove or reset an  account. Three limits worth stating. A cmdlet typed into a PowerShell session  that is already running creates no process and is invisible here; the brief's  other log source, Security 4723/4724/4740, records the account change itself  and would see it, but it is a different logsource and this rule does not use  it. The bare `net user <name> <password>` form has no flag to anchor on and  is not selected. And Sigma models no aggregation, so a single service-desk  reset and a sweep that resets every account in the domain — the LockerGoga  behaviour this technique is named for — produce identical single events here,  which is why the level sits at the bottom of the scale. MITRE's UserContext,  TimeWindow and ParentProcessName knobs all need a baseline or a time window  that Sigma cannot express, so none of them is encoded. The brief's  process-creation source for this analytic is Sysmon EventID 1; confirm  process creation is not filtered out of the running Sysmon config before  reading an empty result as quiet rather than blind.  UNVERIFIED AS AUTHORED — derived from MITRE ATT&CK DET0120, not hand-written and not tested by its author. Any lab result is on this rule's own page.references:  - https://attack.mitre.org/techniques/T1531  - https://attack.mitre.org/detectionstrategies/DET0120author: Siemphony pipeline (machine-derived from MITRE ATT&CK v19.2)date: 2026-08-16tags:  - attack.impact  - attack.t1531logsource:  category: process_creation  product: windowsdetection:  selection_net_delete:    Image|endswith:      - '\net.exe'      - '\net1.exe'    CommandLine|contains|all:      - ' user '      - 'delete'  selection_net_disable:    Image|endswith:      - '\net.exe'      - '\net1.exe'    CommandLine|contains|all:      - ' user '      - 'active:no'  selection_local_cmdlet:    CommandLine|contains:      - 'Remove-LocalUser'      - 'Disable-LocalUser'      - 'Set-LocalUser'  selection_directory_cmdlet:    CommandLine|contains:      - 'Remove-ADUser'      - 'Disable-ADAccount'      - 'Set-ADAccountPassword'  selection_wmi_disable:    Image|endswith: '\wmic.exe'    CommandLine|contains|all:      - 'useraccount'      - 'disabled='  condition: 1 of selection*falsepositives:  - "Service-desk password resets, which run as Set-ADAccountPassword or Set-LocalUser from an administrator's shell or a self-service reset portal's worker. On any estate with a help desk this is the highest-volume match by a wide margin, and it is why this rule is rated low rather than higher."  - "Scheduled joiner-mover-leaver automation that disables an account on the leave date and deletes it after a retention period, using Disable-ADAccount and Remove-ADUser under a known service account on a management server."  - "Build, imaging and provisioning scripts that remove the temporary install account at the end of a run with net user <name> /delete, which fires once per machine build."  - "Hardening baselines that disable the built-in guest or local administrator account with net user guest /active:no, firing on every host the baseline is first applied to."level: low

Sentinel · KQL

Run this as a search.

DeviceProcessEvents| where (((FolderPath endswith "\\net.exe" or FolderPath endswith "\\net1.exe") and (ProcessCommandLine contains " user " and ProcessCommandLine contains "delete")) or ((FolderPath endswith "\\net.exe" or FolderPath endswith "\\net1.exe") and (ProcessCommandLine contains " user " and ProcessCommandLine contains "active:no")) or (ProcessCommandLine contains "Remove-LocalUser" or ProcessCommandLine contains "Disable-LocalUser" or ProcessCommandLine contains "Set-LocalUser") or (ProcessCommandLine contains "Remove-ADUser" or ProcessCommandLine contains "Disable-ADAccount" or ProcessCommandLine contains "Set-ADAccountPassword") or (FolderPath endswith "\\wmic.exe" and (ProcessCommandLine contains "useraccount" and ProcessCommandLine contains "disabled=")))

Splunk · SPL

Run this as a search.

index=* (((Image="*\\net.exe" OR Image="*\\net1.exe") AND (CommandLine="* user *" AND CommandLine="*delete*")) OR ((Image="*\\net.exe" OR Image="*\\net1.exe") AND (CommandLine="* user *" AND CommandLine="*active:no*")) OR (CommandLine="*Remove-LocalUser*" OR CommandLine="*Disable-LocalUser*" OR CommandLine="*Set-LocalUser*") OR (CommandLine="*Remove-ADUser*" OR CommandLine="*Disable-ADAccount*" OR CommandLine="*Set-ADAccountPassword*") OR (Image="*\\wmic.exe" AND (CommandLine="*useraccount*" AND CommandLine="*disabled=*")))

Elastic · ES|QL

Run this as a search.

FROM logs-*| WHERE (((TO_LOWER(process.executable) LIKE "*\\\\net.exe" OR TO_LOWER(process.executable) LIKE "*\\\\net1.exe") AND (TO_LOWER(process.command_line) LIKE "* user *" AND TO_LOWER(process.command_line) LIKE "*delete*")) OR ((TO_LOWER(process.executable) LIKE "*\\\\net.exe" OR TO_LOWER(process.executable) LIKE "*\\\\net1.exe") AND (TO_LOWER(process.command_line) LIKE "* user *" AND TO_LOWER(process.command_line) LIKE "*active:no*")) OR (TO_LOWER(process.command_line) LIKE "*remove-localuser*" OR TO_LOWER(process.command_line) LIKE "*disable-localuser*" OR TO_LOWER(process.command_line) LIKE "*set-localuser*") OR (TO_LOWER(process.command_line) LIKE "*remove-aduser*" OR TO_LOWER(process.command_line) LIKE "*disable-adaccount*" OR TO_LOWER(process.command_line) LIKE "*set-adaccountpassword*") OR (TO_LOWER(process.executable) LIKE "*\\\\wmic.exe" AND (TO_LOWER(process.command_line) LIKE "*useraccount*" AND TO_LOWER(process.command_line) LIKE "*disabled=*")))

Wazuh · XML rule

Deploy to your manager — this is a rule, not a search.

<group name="sigma,windows,process_creation,">  <!-- Rule ids must be unique on your manager; 100000+ is the user range. -->  <!-- 5 rules: the Sigma condition ORs across different fields,       which one rule cannot express. Any one matching is a hit. -->  <rule id="100000" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="Image" type="pcre2">(?i)(\\net\.exe$|\\net1\.exe$)</field>    <field name="CommandLine" type="pcre2">(?i)(?=.*(?: user ))(?=.*(?:delete)).*</field>    <description>Account disabled, deleted or reset from a command line (1/5)</description>    <mitre>      <id>T1531</id>    </mitre>  </rule>   <rule id="100001" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="Image" type="pcre2">(?i)(\\net\.exe$|\\net1\.exe$)</field>    <field name="CommandLine" type="pcre2">(?i)(?=.*(?: user ))(?=.*(?:active:no)).*</field>    <description>Account disabled, deleted or reset from a command line (2/5)</description>    <mitre>      <id>T1531</id>    </mitre>  </rule>   <rule id="100002" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(Remove-LocalUser|Disable-LocalUser|Set-LocalUser)</field>    <description>Account disabled, deleted or reset from a command line (3/5)</description>    <mitre>      <id>T1531</id>    </mitre>  </rule>   <rule id="100003" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="CommandLine" type="pcre2">(?i)(Remove-ADUser|Disable-ADAccount|Set-ADAccountPassword)</field>    <description>Account disabled, deleted or reset from a command line (4/5)</description>    <mitre>      <id>T1531</id>    </mitre>  </rule>   <rule id="100004" level="5">    <!-- Set <if_sid> to the decoder/base rule for windows so this only evaluates relevant events. -->    <field name="Image" type="pcre2">(?i)\\wmic\.exe$</field>    <field name="CommandLine" type="pcre2">(?i)(?=.*(?:useraccount))(?=.*(?:disabled=)).*</field>    <description>Account disabled, deleted or reset from a command line (5/5)</description>    <mitre>      <id>T1531</id>    </mitre>  </rule></group>

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