Detection rules › Splunk
SoftPerfect Network Scanner Execution (Windows Event Log)
SoftPerfect Network Scanner is a free port scanner that can be run without installation. Due to its portability, it is an attractive tool for threat actors during post-compromise discovery activities as reported by DFIR. This use case detects executions of netscan.exe, netscan32.exe, or netscan64.exe. While the tool itself is not considered malicious, unexpected use should be investigated as it may indicate unauthorized discovery activity
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Discovery |
References
- https://www.softperfect.com/products/networkscanner/
- https://thedfirreport.com/2023/10/30/netsupport-intrusion-results-in-domain-compromise/
- https://thedfirreport.com/2020/07/13/ransomware-again-but-we-changed-the-rdp-port/
- https://thedfirreport.com/2023/08/28/html-smuggling-leads-to-domain-wide-ransomware/
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
id: '24804.45866'
title: SoftPerfect Network Scanner Execution
description: 'SoftPerfect Network Scanner is a free port scanner that can be run without
installation. Due to its portability, it is an attractive tool for threat actors
during post-compromise discovery activities as reported by DFIR. This use case detects
executions of netscan.exe, netscan32.exe, or netscan64.exe. While the tool itself
is not considered malicious, unexpected use should be investigated as it may indicate
unauthorized discovery activity. -- Software Association: Akira'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) "netscan" | where match(process_name, "(?i)\x5cnetscan(32|64)?\.exe")
or match(process_path, "(?i)\x5cnetscan_portable") | table _time, host, user, process,
process_*, parent_process, parent_process_*, user | bin span=1s | stats values(*)
as * by _time, host '
techniques:
- discovery:network service discovery
technique_id:
- T1046
data_category:
- Windows event logs
references:
- https://www.softperfect.com/products/networkscanner/
- https://thedfirreport.com/2023/10/30/netsupport-intrusion-results-in-domain-compromise/
- https://thedfirreport.com/2020/07/13/ransomware-again-but-we-changed-the-rdp-port/
- https://thedfirreport.com/2023/08/28/html-smuggling-leads-to-domain-wide-ransomware/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) "netscan"
Stage 2: where
| where match(process_name, "(?i)\x5cnetscan(32|64)?\.exe") or match(process_path, "(?i)\x5cnetscan_portable")
Stage 3: table
| table _time, host, user, process, process_*, parent_process, parent_process_*, user
Stage 4: bucket
| bin span=1s
Stage 5: stats
| stats values(*) as * by _time, host
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
EventCode | eq |
| field:"EventID" kind:eq value:"4688" |
process_name | regex_match |
| field:"process_name" kind:regex_match |
process_path | regex_match |
| field:"process_name" kind:regex_match |
Search terms
These SPL tokens match against raw event text.
| Stage | Term |
|---|---|
| 1 | "<EventID>4688<" |
| 1 | "netscan" |