CmdID / Rules / Windows

Suspicious Sysmon as Execution Parent

A Sigma rule for process creation on Windows, from SigmaHQ’s emerging threats rules, by Florian Roth (Nextron Systems), Tim Shelton (fp werfault).

high 1 ATT&CK technique 8 programs it names

What it looks for

its detection, as SigmaHQ writes it

detection:
  filter_main_generic:
    Image|contains:
      - ':\Windows\Sysmon.exe'
      - ':\Windows\Sysmon64.exe'
      - ':\Windows\System32\conhost.exe'
      - ':\Windows\System32\WerFault.exe'
      - ':\Windows\System32\WerFaultSecure.exe'
      - ':\Windows\System32\wevtutil.exe'
      - ':\Windows\SysWOW64\wevtutil.exe'
  filter_main_null:
    Image: null
  filter_main_temp_sysmon:
    Image|contains: '\AppData\Local\Temp\'
    Image|endswith:
      - '\Sysmon.exe'
      - '\Sysmon64.exe'
    Image|startswith: 'C:\Users\'
  selection:
    ParentImage|endswith:
      - '\Sysmon.exe'
      - '\Sysmon64.exe'
  condition: selection and not 1 of filter_main_*

The rule’s detection, its selections and fields in order of name. The whole rule, with its references and false positives, is on SigmaHQ, by Florian Roth (Nextron Systems), Tim Shelton (fp werfault), under the Detection Rule License 1.1. CmdID evaluates it on a command line alone: a test on what a command line cannot show, such as the parent process or the user, is not met.

None of the everyday examples and documented commands on CmdID’s program pages trips it. To see whether a command line does, paste it into CmdID.

Programs and files it names

their pages here

conhost.exesysmonwevtutilSysmon.exeSysmon64.exeWerFault.exeWerFaultSecure.exewevtutil.exe

ATT&CK

the techniques it is tagged with

T1068Exploitation for Privilege Escalation

Suspicious Sysmon as Execution Parent

What it looks for

Programs and files it names

ATT&CK

Other rules for T1068 Exploitation for Privilege Escalation