diff --git a/rules/windows/process_creation/win_susp_psexex_paexec_escalate_system.yml b/rules/windows/process_creation/win_susp_psexex_paexec_escalate_system.yml new file mode 100644 index 000000000..1d194067c --- /dev/null +++ b/rules/windows/process_creation/win_susp_psexex_paexec_escalate_system.yml @@ -0,0 +1,29 @@ +title: PsExec/PAExec Escalation to LOCAL SYSTEM +id: 8834e2f7-6b4b-4f09-8906-d2276470ee23 +status: experimental +description: Detects suspicious flags used by PsExec and PAExec to escalate a command line to LOCAL_SYSTEM rights +references: + - https://docs.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 +author: Florian Roth +date: 2021/11/23 +logsource: + category: process_creation + product: windows +detection: + selection_cmd_to_system: # Escalation to LOCAL_SYSTEM + CommandLine|endswith: ' -s cmd.exe' + selection_supporting_flags: + CommandLine|contains: + - 'PsExec' + - 'PAExec' + - 'accepteula' + - 'cmd /c ' + condition: selection_supporting_flags and selection_cmd_to_system +falsepositives: + - Admins that use PsExec or PAExec to escalate to the SYSTEM account for maintenance purposes (rare) +level: high +tags: + - attack.develop_capabilities + - attack.t1587.001 \ No newline at end of file diff --git a/rules/windows/process_creation/win_susp_psexex_paexec_flags.yml b/rules/windows/process_creation/win_susp_psexex_paexec_flags.yml index 51926aa0f..c6b92318d 100644 --- a/rules/windows/process_creation/win_susp_psexex_paexec_flags.yml +++ b/rules/windows/process_creation/win_susp_psexex_paexec_flags.yml @@ -8,21 +8,19 @@ references: - https://www.fireeye.com/blog/threat-research/2020/10/kegtap-and-singlemalt-with-a-ransomware-chaser.html author: Florian Roth date: 2021/05/22 +modified: 2021/11/23 logsource: category: process_creation product: windows detection: selection_flags_1: # Escalation to LOCAL_SYSTEM - CommandLine|contains|all: - - '\\127.0.0.1' - - ' -s ' - - 'cmd.exe' + CommandLine|endswith: ' -s cmd.exe' selection_flags_2: CommandLine|contains|all: # Accepting EULA in commandline - often used in automated attacks - - ' /accepteula ' - - 'cmd /c ' + - 'accepteula' - ' -u ' - ' -p ' + - ' \\' filter: CommandLine|contains: - 'paexec'