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

66 lines
2.6 KiB
YAML

name: Services Escalate Exe
id: c448488c-b7ec-11eb-8253-acde48001122
version: 1
date: '2021-05-18'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following analytic identifies the use of `svc-exe` with Cobalt Strike.
The behavior typically follows after an adversary has already gained initial access
and is escalating privileges. Using `svc-exe`, a randomly named binary will be downloaded
from the remote Teamserver and placed on disk within `C:\Windows\400619a.exe`. Following,
the binary will be added to the registry under key `HKLM\System\CurrentControlSet\Services\400619a\`
with multiple keys and values added to look like a legitimate service. Upon loading,
`services.exe` will spawn the randomly named binary from `\\127.0.0.1\ADMIN$\400619a.exe`.
The process lineage is completed with `400619a.exe` spawning rundll32.exe, which
is the default `spawnto_` value for Cobalt Strike. The `spawnto_` value is arbitrary
and may be any process on disk (typically system32/syswow64 binary). The `spawnto_`
process will also contain a network connection. During triage, review parallel procesess
and identify any additional file modifications.
data_source:
- Sysmon Event ID 1
search:
selection1:
Processes.process_path: '*admin$*'
ParentImage: services.exe
condition: selection1
how_to_implement: To successfully implement this search, you will need to ensure that
DNS data is populating the Network_Resolution data model.
known_false_positives: False positives should be limited as `services.exe` should
never spawn a process from `ADMIN$`. Filter as needed.
references:
- https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
- https://attack.mitre.org/techniques/T1548/
- https://hstechdocs.helpsystems.com/manuals/cobaltstrike/current/userguide/index.htm#cshid=1085
tags:
analytic_story:
- Cobalt Strike
asset_type: Endpoint
confidence: 95
impact: 80
message: A service process $parent_process_name$ with process path $process_path$
in host $dest$
mitre_attack_id:
- T1548
observable:
- name: Processes.dest
type: Hostname
role:
- Victim
- name: Processes.user
type: User
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
risk_score: 76
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1055/cobalt_strike/windows-sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: xmlwineventlog