Linux Docker Shell Execution

Name:Linux Docker Shell Execution
id:03b2b286-fa86-4ec9-b1a1-ec19d314bdf7
version:4
date:None
author:Gowthamaraj Rajendran, Splunk, Emil Elsetrønning
status:production
type:Anomaly
Description:This detection identifies shell execution activity associated with Docker containers on Linux systems. Specifically, it monitors for interactive or non-interactive shell processes (e.g., `/bin/bash`, `/bin/sh`, `/bin/zsh`) launched via Docker commands such as `docker exec`, or through container entrypoint overrides. Shell execution inside a container may indicate administrative troubleshooting activity. However, it can also represent post-exploitation behavior, where an attacker gains access to a container and spawns a shell to execute arbitrary commands, establish persistence, or pivot to the host.
Data_source:

• -Sysmon for Linux EventID 1

search:| tstats `security_content_summariesonly`
count min(_time) as firstTime
max(_time) as lastTime
from datamodel=Endpoint.Processes where
Processes.process_name=docker*
Processes.process="* exec *"
Processes.process IN (
"* /bin/bash *",
"* /bin/dash *",
"* /bin/sh *",
"* /bin/zsh *",
"* bash *",
"* bash",
"* dash *",
"* dash",
"* sh *",
"* sh",
"* zsh *",
"* zsh"
)
by Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec
Processes.parent_process_guid Processes.parent_process_id
Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id
Processes.process_integrity_level Processes.process_name
Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `linux_docker_shell_execution_filter`

how_to_implement:The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives:False positives are present based on automated tooling or system administrative usage. Filter as needed.
References:
  -https://docs.docker.com/reference/cli/docker/container/exec/
  -https://gtfobins.github.io/gtfobins/docker/
drilldown_searches:
 name:'View the detection results for - "$dest$"'
 search:'%original_detection_search% | search dest = "$dest$"'
 earliest_offset:'$info_min_time$'
 latest_offset:'$info_max_time$'
 name:'View risk events for the last 7 days for - "$dest$"'
 search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
 earliest_offset:'7d'
 latest_offset:'0'
analytic_story:['Linux Privilege Escalation', 'Linux Living Off The Land']

asset_type:Endpoint

mitre_attack_id:['T1059.013']

product:['Splunk Enterprise', 'Splunk Enterprise Security', 'Splunk Cloud']

category:endpoint

security_domain:endpoint

tags:

tests:
 name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548/docker/sysmon_linux.log
  source: Syslog:Linux-Sysmon/Operational
  sourcetype: sysmon:linux
 test_type:'unit'
manual_test:None