Files
splunk-security_content/dev/endpoint/allow_network_discovery_in_firewall.yml
2023-01-20 13:24:15 +01:00

62 lines
2.0 KiB
YAML

name: Allow Network Discovery In Firewall
id: ccd6a38c-d40b-11eb-85a5-acde48001122
version: 2
date: '2021-06-23'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: This search is to detect a suspicious modification to the firewall to
allow network discovery on a machine. This technique was seen in couple of ransomware
(revil, reddot) to discover other machine connected to the compromised host to encrypt
more files.
data_source:
- Sysmon Event ID 1
search:
selection1:
OriginalFileName: netsh.exe
selection2:
Image|endswith: netsh.exe
selection3:
CommandLine: '*firewall*'
selection4:
CommandLine: '*group='
condition: (selection1 or selection2) and selection3 and selection4
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: network admin may modify this firewall feature that may cause
this rule to be triggered.
references:
- https://community.fortinet.com:443/t5/FortiEDR/How-FortiEDR-detects-and-blocks-Revil-Ransomware-aka-sodinokibi/ta-p/189638?externalID=FD52469
- https://app.any.run/tasks/c0f98850-af65-4352-9746-fbebadee4f05/
tags:
analytic_story:
- Ransomware
- Revil Ransomware
asset_type: Endpoint
confidence: 50
impact: 50
message: ''
mitre_attack_id:
- T1562.007
- T1562
observable:
- name: user
type: User
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
risk_score: 25.0
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/ransomware_ttp/data2/windows-sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: xmlwineventlog