Detection rules › Splunk
Network Share Connection Removal (PowerShell)
Adversaries may remove share connections that are no longer useful in order to clean up traces of their operation
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Stealth | T1070.005 Indicator Removal: Network Share Connection Removal |
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Rule body yaml
id: '10325.24411'
title: Network Share Connection Removal
description: 'Adversaries may remove share connections that are no longer useful in
order to clean up traces of their operation. Atomics T1070.005 Test #2 Atomics T1070.005
Test #3 Atomics T1070.005 Test #5'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4103) OR
"<EventID>4103<" OR TERM(EventCode=4104) OR "<EventID>4104<") TERM(Remove-SmbShare)
OR TERM(Remove-Fileshare) | table _time, host, user process, process_* | bin span=1s
| stats values(*) as * by _time, host '
techniques:
- defense-evasion:indicator removal:network share connection removal
technique_id:
- T1070.005
data_category:
- PowerShell logs
references:
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1070.005/T1070.005.md#atomic-test-3---remove-network-share-powershell
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4103) OR "<EventID>4103<" OR TERM(EventCode=4104) OR "<EventID>4104<") TERM(Remove-SmbShare) OR TERM(Remove-Fileshare)
Stage 2: table
| table _time, host, user process, 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.
| Field | Kind | Values |
|---|---|---|
EventCode | eq |
|
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>4103<" |
| 1 | TERM |
| 1 | "<EventID>4104<" |
| 1 | "Remove-SmbShare" |
| 1 | "Remove-Fileshare" |