mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
Patrick Bareiss
117 lines
4.0 KiB
YAML
117 lines
4.0 KiB
YAML
asset_type: Endpoint
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confidence: medium
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creation_date: '2018-09-11'
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data_metadata:
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data_models:
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- Endpoint
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data_source:
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- Endpoint Intel
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providing_technologies:
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- Carbon Black Response
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- CrowdStrike Falcon
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- Sysmon
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- Tanium
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- Ziften
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description: This search looks for specific command-line arguments that may indicate
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the execution of tools made by Nirsoft, which are legitimate, but may be abused
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by attackers.
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detect:
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splunk:
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correlation_rule:
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notable:
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nes_fields: dest, user, process
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rule_description: This search looks for specific arguments passed via the
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command line and detects execution of tools built by NirSoft, which are
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often abused by attackers.
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rule_title: Potential abuse of NirSoft tools on $dest$
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risk:
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risk_object: dest
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risk_object_type:
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- system
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risk_score: 80
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schedule:
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cron_schedule: 0 * * * *
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earliest_time: -70m@m
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latest_time: -10m@m
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search: '| tstats `summariesonly` count min(_time) values(Processes.process)
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as process max(_time) as lastTime from datamodel=Endpoint.Processes where
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(Processes.process="* /stext *" OR Processes.process="* /scomma *" ) by Processes.parent_process
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Processes.process_name Processes.user | `drop_dm_object_name(Processes)` |
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`ctime(firstTime)` |`ctime(lastTime)`'
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suppress:
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suppress_fields: dest, process
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suppress_period: 28800s
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eli5: The search looks for process-creation events accompanied by specific command-line
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arguments ("scomma" and "stext"). These parameters may be leveraged by a set of
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free, legitimate tools built by NirSoft. Attackers have been seen abusing the tools'
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capabilities to steal passwords, set up key loggers, recover account information
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from mail clients, and conduct other nefarious activities. The search will identify
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the count, the first and last times a process is executed, the command-line arguments,
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and the parent process.
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entities:
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- dest
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how_to_implement: You must be ingesting endpoint data that tracks process activity,
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including parent-child relationships from your endpoints to populate the Endpoint
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data model in the Processes node. The command-line arguments are mapped to the "process"
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field in the Endpoint data model.
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id: 1297fb80-f42a-4q4a-9c8b-78c061417cf6
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investigations:
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- id: bc91a8cf-35e7-4bb2-8140-e756cc06fd76
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name: Get Authentication Logs For Endpoint
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type: splunk
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- id: fecf2918-670d-4f1c-872b-3d7317a41bf9
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name: Get Parent Process Info
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type: splunk
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- id: fdcfb369-1725-4c24-824a-22972d7f0d55
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name: Get Risk Modifiers For User
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type: splunk
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- id: bc91a8cf-35e7-4bb2-8140-e756cc06fd71
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name: Get Process Info
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type: splunk
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- id: 3d6c3213-5fff-4a1e-b57d-b24c262171e7
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name: Get Notable History
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type: splunk
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- id: f3fb4d1b-5f33-4b01-b541-c7af9534c242
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name: Get Notable Info
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type: splunk
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- id: fdcfb369-1725-4c24-824a-22972d7f0d65
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name: Get Risk Modifiers For Endpoint
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type: splunk
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- id: bc91a8cf-35e7-4bb2-8140-e756cc06fd74
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name: Get User Information from Identity Table
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type: splunk
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- id: bc91a8cf-35e7-4bb2-8140-e756cc06fd22
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name: Investigate Web Activity From Host
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type: splunk
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known_false_positives: While legitimate, these NirSoft tools are prone to abuse. You
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should verfiy that the tool was used for a legitimate purpose.
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maintainers:
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- company: Splunk
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email: bpatel@splunk.com
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name: Bhavin Patel
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mappings:
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cis20:
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- CIS 3
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kill_chain_phases:
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- Installation
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- Actions on Objectives
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mitre_attack:
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- Discovery
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- Execution
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- Lateral Movement
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- Third-party Software
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- Account Discovery
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nist:
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- PR.IP
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modification_date: '2018-12-03'
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name: Detection of tools built by NirSoft
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original_authors:
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- company: Splunk
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email: bpatel@splunk.com
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name: Bhavin Patel
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references: []
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security_domain: endpoint
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spec_version: 2
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type: splunk
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version: '2.0'
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