Detection rules › Splunk
.msc Executed from Unusual Location (Windows Event Log)
Threat actors may abuse mmc.exe to proxy execution of malicious .msc files. Microsoft Management Console (MMC) is a binary that may be signed by Microsoft and is used in several ways in either its GUI or in a command prompt. MMC can be used to create, open, and save custom consoles that contain administrative tools created by Microsoft, called snap-ins. These snap-ins may be used to manage Windows systems locally or remotely. MMC can also be used to open Microsoft created .msc files to manage system configuration. This use case detects mmc.exe executions referencing .msc files outside of C:\Windows\system32 or C:\Windows\SysWOW64.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1218.014 System Binary Proxy Execution: MMC |
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body yaml
id: '32363.57556'
title: .msc Executed from Unusual Location
description: 'Threat actors may abuse mmc.exe to proxy execution of malicious .msc
files. Microsoft Management Console (MMC) is a binary that may be signed by Microsoft
and is used in several ways in either its GUI or in a command prompt. MMC can be
used to create, open, and save custom consoles that contain administrative tools
created by Microsoft, called snap-ins. These snap-ins may be used to manage Windows
systems locally or remotely. MMC can also be used to open Microsoft created .msc
files to manage system configuration. This use case detects mmc.exe executions referencing
.msc files outside of C:\Windows\system32 or C:\Windows\SysWOW64. '
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) "mmc.exe" ".msc" | regex process="(?i)\.msc"|
regex process!="(?i)C:\x5cWindows\x5c(system32|syswow64)\x5c\w+\.msc" | table _time,
host, user, process | bin span=1s | stats values(*) as * by _time, host '
techniques:
- defense-evasion:system binary proxy execution:mmc
technique_id:
- T1218.014
data_category:
- Process command-line parameters
- Windows event logs
references:
- https://www.itechtics.com/enable-gpedit-windows-10-home/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) "mmc.exe" ".msc"
Stage 2: regex
| regex process="(?i)\.msc"
Stage 3: regex
| regex process!="(?i)C:\x5cWindows\x5c(system32|syswow64)\x5c\w+\.msc"
Stage 4: table
| table _time, host, user, process
Stage 5: bucket
| bin span=1s
Stage 6: stats
| stats values(*) as * by _time, host
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
process | regex_match | "(?i)C:\x5cWindows\x5c(system32|syswow64)\x5c\w+.msc" |
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.
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 | "mmc.exe" |
| 1 | ".msc" |