Detection rules › Splunk
Impacket Lateral Movement Activity (Windows Event Log)
Impacket is a collection of Python classes for working with network protocols, primarily focused on providing tools and scripts that facilitate the interaction with network services and protocols commonly used in network penetration testing and red teaming. wmiexec, smbexec, and dcomexec are specific tools within the Impacket suite that use various protocols to execute commands on remote systems. This use case detects specific behavior patterns associated with Impacket tools wmiexec, smbexec, and dcomexec.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Lateral Movement | T1021.002 Remote Services: SMB/Windows Admin Shares, T1210 Exploitation of Remote Services |
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
id: '33319.58975'
title: Impacket Lateral Movement Activity
description: Impacket is a collection of Python classes for working with network protocols,
primarily focused on providing tools and scripts that facilitate the interaction
with network services and protocols commonly used in network penetration testing
and red teaming. wmiexec, smbexec, and dcomexec are specific tools within the Impacket
suite that use various protocols to execute commands on remote systems. This use
case detects specific behavior patterns associated with Impacket tools wmiexec,
smbexec, and dcomexec.
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) ("&1" OR "&1") (("wmiprvse.exe" OR "mmc.exe"
OR "explorer.exe" OR "services.exe") (("cmd.exe" OR "powershell.exe" OR "pwsh.exe")
("/Q" "/c") OR ("-c" OR "-command"))) OR ("svchost" ("cmd" OR "powershell" OR "pwsh")
("/C" OR -c" OR -command") "Windows\\Temp") | where ((match(parent_process_name,
"(?i)(wmiprvse|mmc|explorer|services)\.exe") and match(process, "(?i)(cmd|powershell|pwsh)\.exe\s(\/Q)?\s(\/|-)c(ommand)?\s"))
or (match(parent_process_name, "(?i)svchost\.exe") and match(process, "(?i)(powershell|pwsh|cmd)\.exe\s(\/|-)c(ommand)?\s.+Windows\x5cTemp\x5c")))
| table _time, host, user, parent_*, process, process_* | bin span=1s | stats values(*)
as * by _time, host '
techniques:
- lateral-movement:remote services:smb/windows admin shares
- lateral-movement:exploitation of remote services
technique_id:
- T1021.002
- T1210
data_category:
- Process command-line parameters
- Windows event logs
references:
- https://attack.mitre.org/techniques/T1047/
- https://attack.mitre.org/techniques/T1021/003/
- https://detection.fyi/sigmahq/sigma/windows/process_creation/proc_creation_win_hktl_impacket_lateral_movement/?query=10c14723-61c7-4c75-92ca-9af245723ad2
- https://github.com/fortra/impacket/tree/master
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) ("&1" OR "&1") (("wmiprvse.exe" OR "mmc.exe" OR "explorer.exe" OR "services.exe") (("cmd.exe" OR "powershell.exe" OR "pwsh.exe") ("/Q" "/c") OR ("-c" OR "-command"))) OR ("svchost" ("cmd" OR "powershell" OR "pwsh") ("/C" OR -c" OR -command") "Windows\\Temp")
Stage 2: where
| where ((match(parent_process_name, "(?i)(wmiprvse|mmc|explorer|services)\.exe") and match(process, "(?i)(cmd|powershell|pwsh)\.exe\s(\/Q)?\s(\/|-)c(ommand)?\s")) or (match(parent_process_name, "(?i)svchost\.exe") and match(process, "(?i)(powershell|pwsh|cmd)\.exe\s(\/|-)c(ommand)?\s.+Windows\x5cTemp\x5c")))
Stage 3: table
| table _time, host, user, parent_*, process, process_*
Stage 4: bucket
| bin span=1s
Stage 5: stats
| stats values(*) as * by _time, host
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 |
|---|---|---|
EventCode | eq |
|
parent_process_name | match |
|
process | match |
|
Search terms
Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.
| Stage | Term |
|---|---|
| 1 | TERM |
| 1 | "<EventID>4688<" |
| 1 | "&1" |
| 1 | "&1" |
| 1 | "wmiprvse.exe" |
| 1 | "mmc.exe" |
| 1 | "explorer.exe" |
| 1 | "services.exe" |
| 1 | "cmd.exe" |
| 1 | "powershell.exe" |
| 1 | "pwsh.exe" |
| 1 | "/Q" |
| 1 | "/c" |
| 1 | "-c" |
| 1 | "-command" |
| 1 | "svchost" |
| 1 | "cmd" |
| 1 | "powershell" |
| 1 | "pwsh" |
| 1 | "/C" |
| 1 | -c" |
| 1 | -command" |
| 1 | "Windows\\Temp" |