Detection rules › Sigma

Metasploit Or Impacket Service Installation Via SMB PsExec

Severity
high
Author
Bartlomiej Czyz, Relativity
Source
upstream

Detects usage of Metasploit SMB PsExec (exploit/windows/smb/psexec) and Impacket psexec.py by triggering on specific service installation

MITRE ATT&CK coverage

TacticTechniques
ExecutionT1569.002 System Services: Service Execution
Lateral MovementT1021.002 Remote Services: SMB/Windows Admin Shares, T1570 Lateral Tool Transfer

Event coverage

ProviderEvent IDTitle
Security-Auditing4697A service was installed in the system.

Stages and Predicates

Stage 1: selection

ServiceFileName|re: '^%systemroot%\\[a-zA-Z]{8}\.exe$'
ServiceName|re: '(^[a-zA-Z]{4}$)|(^[a-zA-Z]{8}$)|(^[a-zA-Z]{16}$)'
ServiceStartType: 3
ServiceType: 0x10

Stage 2: not filter

ServiceName: PSEXESVC

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
ServiceFileNameregex_match
  • ^%systemroot%\\[a-zA-Z]{8}\.exe$
ServiceNameeq
  • PSEXESVC corpus 2 (sigma 2)
ServiceNameregex_match
  • (^[a-zA-Z]{4}$)|(^[a-zA-Z]{8}$)|(^[a-zA-Z]{16}$)
ServiceStartTypeeq
  • 3
ServiceTypeeq
  • 0x10

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.