Suspicious New Service Creation

Severity: high
Author: Nasreddine Bencherchali (Nextron Systems)
Source: upstream

Detects creation of a new service via "sc" command or the powershell "new-service" cmdlet with suspicious binary paths

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	`T1543.003` Create or Modify System Process: Windows Service
Privilege Escalation	`T1543.003` Create or Modify System Process: Windows Service

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation
Security-Auditing	4688	A new process has been created.

Stages and Predicates

Stage 1: `1 of selection_sc`

CommandLine|contains: 'binPath='
CommandLine|contains: create
Image|endswith: '\sc.exe'

Stage 2: `1 of selection_posh`

CommandLine|contains: -BinaryPathName
CommandLine|contains: New-Service

Stage 3: `susp_binpath`

or:
CommandLine|contains: 'C:\Users\Public'
CommandLine|contains: 'C:\Windows\TEMP\'
CommandLine|contains: '\AppData\Local\Temp'
CommandLine|contains: '\Desktop\'
CommandLine|contains: '\Downloads\'
CommandLine|contains: '\Microsoft\Windows\Start Menu\Programs\Startup\'
CommandLine|contains: 'cmd '
CommandLine|contains: 'cmd.exe /c'
CommandLine|contains: 'cmd.exe /k'
CommandLine|contains: 'cmd.exe /r'
CommandLine|contains: cscript
CommandLine|contains: dllhost
CommandLine|contains: mshta
CommandLine|contains: powershell
CommandLine|contains: rundll32
CommandLine|contains: svchost
CommandLine|contains: wscript

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.

Field	Kind	Values
`CommandLine`	match	`-BinaryPathName` corpus 2 (sigma 2) `C:\Users\Public` corpus 2 (sigma 2) `C:\Windows\TEMP\` corpus 3 (sigma 3) `New-Service` corpus 2 (sigma 2) `\AppData\Local\Temp` corpus 8 (sigma 8) `\Desktop\` corpus 11 (sigma 11) `\Downloads\` corpus 12 (sigma 12) `\Microsoft\Windows\Start Menu\Programs\Startup\` corpus 3 (sigma 3) `binPath=` `cmd` corpus 2 (sigma 2) `cmd.exe /c` corpus 3 (sigma 3) `cmd.exe /k` corpus 3 (sigma 3) `cmd.exe /r` corpus 3 (sigma 3) `create` corpus 8 (sigma 8) `cscript` corpus 12 (sigma 12) `dllhost` corpus 2 (sigma 2) `mshta` corpus 11 (sigma 11) `powershell` corpus 16 (sigma 16) `rundll32` corpus 19 (sigma 19) `svchost` corpus 2 (sigma 2) `wscript` corpus 12 (sigma 12)
`Image`	ends_with	`\sc.exe` corpus 17 (sigma 17)