Detection rules › Splunk
Msiexec Abuse (Windows Event Log)
Adversaries may abuse msiexec.exe to proxy execution of malicious payloads. Msiexec.exe is the command-line utility for the Windows Installer and is thus commonly associated with executing installation packages (.msi). This use case looks for msiexec launching filetypes other than ".msi"
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1218.007 System Binary Proxy Execution: Msiexec |
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
id: '6847.8062'
title: Msiexec Abuse
description: 'Adversaries may abuse msiexec.exe to proxy execution of malicious payloads.
Msiexec.exe is the command-line utility for the Windows Installer and is thus commonly
associated with executing installation packages (.msi). This use case looks for
msiexec launching filetypes other than ".msi" Software Association: Raspberry Robin,
Zloader Atomics T1218.007 Test #9 Atomics T1218.007 Test #10'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) TERM(msiexec) NOT ".msi" | regex process="(?i)msiexec.*?\.\w{2,5}"|
table _time, host, user parent_*, process, process_*, signature_id | bin span=1s
| stats values(*) as * by _time, host | eventstats dc(process) as dc_process by
host | where dc_process < 10 '
techniques:
- defense-evasion:system binary proxy execution:msiexec
technique_id:
- T1218.007
data_category:
- Windows event logs
- Process command-line parameters
references:
- https://news.sophos.com/en-us/2020/05/21/ragnar-locker-ransomware-deploys-virtual-machine-to-dodge-security/
- https://lolbas-project.github.io/lolbas/Binaries/Msiexec/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) TERM(msiexec) NOT ".msi"
Stage 2: regex
| regex process="(?i)msiexec.*?\.\w{2,5}"
Stage 3: table
| table _time, host, user parent_*, process, process_*, signature_id
Stage 4: bucket
| bin span=1s
Stage 5: stats
| stats values(*) as * by _time, host
Stage 6: eventstats
| eventstats dc(process) as dc_process by host
Stage 7: where
| where dc_process < 10
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 |
|
dc_process | lt |
|
process | regex_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 | TERM |
| 1 | msiexec |
| 1 | ".msi" |