Detection rules › Splunk
Potential nanodump execution (Windows Event Log)
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
Event coverage
| Provider | Event | Title |
|---|---|---|
| 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 yaml
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
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 |
|
signature_id | 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>4656<" |
| 1 | "0x1010" |
| 1 | TERM |
| 1 | "<EventID>4663<" |
| 1 | "%%4484" |
| 1 | "lsass.exe" |