Sigma rule: Potential Privilege Escalation To LOCAL SYSTEM

Rule

Title

Potential Privilege Escalation To LOCAL SYSTEM

Status

test

Level

high

Author

Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)

Date

2021-05-22

Modified

2024-03-05

File

rules/windows/process_creation/proc_creation_win_sysinternals_susp_psexec_paexec_flags.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects unknown program using commandline flags usually used by tools such as PsExec and PAExec to start programs with SYSTEM Privileges

Log source

product

windows

category

process_creation

Detection

selection:
    # Escalation to LOCAL_SYSTEM
    CommandLine|contains|windash:
        # Note that you don't need to add the ".exe" part when using psexec/paexec
        # The "-" can also be replaced with "/"
        # The order of args isn't important
        # "cmd" can be replaced by "powershell", "pwsh" or any other console like software
        - ' -s cmd'
        - ' -s -i cmd'
        - ' -i -s cmd'
        # Pwsh (For PowerShell 7)
        - ' -s pwsh'
        - ' -s -i pwsh'
        - ' -i -s pwsh'
        # PowerShell (For PowerShell 5)
        - ' -s powershell'
        - ' -s -i powershell'
        - ' -i -s powershell'
filter_main_exclude_coverage:
    # This filter exclude strings covered by 8834e2f7-6b4b-4f09-8906-d2276470ee23
    CommandLine|contains:
        - 'paexec'
        - 'PsExec'
        - 'accepteula'
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

• Weird admins that rename their tools
• Software companies that bundle PsExec/PAExec with their software and rename it, so that it is less embarrassing

Tags

• attack.resource-development
• attack.t1587.001

MITRE ATT&CK ids this rule names

• T1587.001

Related rules

• 8834e2f7-6b4b-4f09-8906-d2276470ee23 (similar)

References

• https://learn.microsoft.com/en-us/sysinternals/downloads/psexec
• https://www.poweradmin.com/paexec/
• https://www.fireeye.com/blog/threat-research/2020/10/kegtap-and-singlemalt-with-a-ransomware-chaser.html

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_sysinternals_susp_psexec_paexec_flags.yml