Potential nanodump execution (Windows Event Log)

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

Nanodump is a flexible tool that creates a minidump of the LSASS process and is commonly used by red teams with cobalt strike. This use case looks for nanodumps default access requests.

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1003` OS Credential Dumping

References

https://github.com/fortra/nanodump

Telemetry coverage

Provider	Record / event type
Security-Auditing	Event ID 4656: A handle to an object was requested.
Security-Auditing	Event ID 4663: An attempt was made to access an object.

Rule body

id: '19348.33710'
title: Potential nanodump execution
description: Nanodump is a flexible tool that creates a minidump of the LSASS process
  and is commonly used by red teams with cobalt strike. This use case looks for nanodumps
  default access requests.
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` ((TERM(EventCode=4656) OR
  "<EventID>4656<") "0x1010" ) OR ((TERM(EventCode=4663) OR "<EventID>4663<") "%%4484"
  ) "lsass.exe" | table _time, host, user process, process_*, signature_id, parent_*
  | bin span=5s | stats values(*) as * by _time, host | where match(signature_id,
  "4656") and match(signature_id, "4663") '
techniques:
- credential-access:os credential dumping
technique_id: T1003
data_category:
- Windows event logs
references:
- https://github.com/fortra/nanodump

Stages and Predicates

Stage 1: `search`

`get_endpoint_data` `get_endpoint_data_winevent` ((TERM(EventCode=4656) OR "<EventID>4656<") "0x1010" ) OR ((TERM(EventCode=4663) OR "<EventID>4663<") "%%4484" ) "lsass.exe"

Stage 2: `table`

| table _time, host, user process, process_*, signature_id, parent_*

Stage 3: `bucket`

| bin span=5s

Stage 4: `stats`

| stats values(*) as * by _time, host

Stage 5: `where`

| where match(signature_id, "4656") and match(signature_id, "4663")

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`EventCode`	eq	`4656` corpus 19 (splunk 15, kusto 4) `4663` corpus 35 (splunk 30, kusto 5)	`field:"EventID" kind:eq`
`signature_id`	regex_match	`"4656"` corpus 3 (splunk 3) `"4663"` corpus 2 (splunk 2)	`field:"signature_id" kind:regex_match`

Search terms

These SPL tokens match against raw event text.

Stage	Term
1	`"<EventID>4656<"`
1	`"0x1010"`
1	`"<EventID>4663<"`
1	`"%%4484"`
1	`"lsass.exe"`