Impacket Lateral Movement smbexec CommandLine Parameters
Description
This analytic focuses on identifying suspicious command-line parameters commonly associated with the use of Impacket wmiexec.py. Impacket is a set of Python classes designed for working with Microsoft network protocols, and it includes several scripts like wmiexec.py, smbexec.py, dcomexec.py, and atexec.py that enable command execution on remote endpoints. These scripts typically utilize administrative shares and hardcoded parameters, which can serve as signatures to detect their usage. Both Red Teams and adversaries may employ Impacket tools for lateral movement and remote code execution purposes. By monitoring for these specific command-line indicators, the analytic aims to detect potentially malicious activities related to Impacket tool usage.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2023-04-25
- Author: Michael Haag, Splunk
- ID: bb3c1bac-6bdf-4aa0-8dc9-068b8b712a76
Annotations
ATT&CK
Kill Chain Phase
- Exploitation
- Installation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=cmd.exe by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id
| `drop_dm_object_name(Processes)`
| where match(process, "(?i)cmd\.exe\s+\/Q\s+\/c") AND match(process,"(?i)echo\s+cd") AND match(process, "(?i)\\__output") AND match(process, "(?i)C:\\\\Windows\\\\[a-zA-Z]{1,8}\\.bat") AND match(process, "\\\\127\.0\.0\.1\\.*")
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `impacket_lateral_movement_smbexec_commandline_parameters_filter`
Macros
The SPL above uses the following Macros:
impacket_lateral_movement_smbexec_commandline_parameters_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- Processes.process_name
- Processes.dest
- Processes.user
- Processes.parent_process_name
- Processes.process
- Processes.process_id
- Processes.parent_process_id
How To Implement
To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the Endpoint
datamodel in the Processes
node. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.
Known False Positives
Although uncommon, Administrators may leverage Impackets tools to start a process on remote systems for system administration or automation use cases.
Associated Analytic Story
- Industroyer2
- Active Directory Lateral Movement
- Prestige Ransomware
- CISA AA22-277A
- Data Destruction
- WhisperGate
- Volt Typhoon
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
63.0 | 90 | 70 | Suspicious command-line parameters on $dest$ may represent lateral movement using smbexec. |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://attack.mitre.org/techniques/T1021/002/
- https://attack.mitre.org/techniques/T1021/003/
- https://attack.mitre.org/techniques/T1047/
- https://attack.mitre.org/techniques/T1053/
- https://attack.mitre.org/techniques/T1053/005/
- https://github.com/SecureAuthCorp/impacket
- https://vk9-sec.com/impacket-remote-code-execution-rce-on-windows-from-linux/
- https://www.microsoft.com/security/blog/2022/01/15/destructive-malware-targeting-ukrainian-organizations/
- https://www.microsoft.com/en-us/security/blog/2023/05/24/volt-typhoon-targets-us-critical-infrastructure-with-living-off-the-land-techniques/
Test Dataset
Replay any dataset to Splunk Enterprise by using our replay.py
tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
source | version: 1