Detection rules › Splunk

MultiDump.exe Execution (Sysmon)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

MultiDump is a post-exploitation tool written in C with a Python handler designed to discreetly dump and extract LSASS memory without triggering Defender alerts. This use case detects rundll32 executions with specific command line parameters unique to MultiDump.

MITRE ATT&CK coverage

References

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

id: '28417.52060'
title: MultiDump.exe Execution
description: MultiDump is a post-exploitation tool written in C with a Python handler
  designed to discreetly dump and extract LSASS memory without triggering Defender
  alerts. This use case detects rundll32 executions with specific command line parameters
  unique to MultiDump.
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_sysmon` (TERM(EventCode=1) OR "<EventID>1<")
  "rundll32" "OpenOptimizationControlPanel" "cleanup" "defrag" "optimize:startup"
  "report" ".dmp" | table _time, host, user, process, process_*, parent_process_*
  | bin span=1s | stats values(*) as * by _time, host '
techniques:
- credential-access:os credential dumping:security account manager
- credential-access:os credential dumping
- credential-access:os credential dumping:lsass memory
technique_id:
- T1003.002
- T1003
- T1003.001
data_category:
- Windows Sysmon
- Process command-line parameters
references:
- https://xre0us.io/posts/multidump/
- https://github.com/Xre0uS/MultiDump?tab=readme-ov-file

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_sysmon` (TERM(EventCode=1) OR "<EventID>1<") "rundll32" "OpenOptimizationControlPanel" "cleanup" "defrag" "optimize:startup" "report" ".dmp"

Stage 2: table

| table _time, host, user, process, process_*, parent_process_*

Stage 3: bucket

| bin span=1s

Stage 4: 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.

FieldKindValues
EventCodeeq
  • 1 corpus 237 (splunk 224, kusto 13)

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.

StageTerm
1TERM
1"<EventID>1<"
1"rundll32"
1"OpenOptimizationControlPanel"
1"cleanup"
1"defrag"
1"optimize:startup"
1"report"
1".dmp"