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[Rule Tuning] Linux DR Tuning - 7 (#5504)

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* [Rule Tuning] Linux DR Tuning - 7

* Update execution_egress_connection_from_entrypoint_in_container.toml

* Update execution_kubernetes_direct_api_request_via_curl_or_wget.toml

* Update rules/linux/execution_perl_tty_shell.toml

* Update execution_perl_tty_shell.toml

* Update rules/linux/execution_unix_socket_communication.toml

* Update execution_file_made_executable_via_chmod_inside_container.toml

* Remove duplicate Crowdstrike data source entry

---------

Co-authored-by: Colson Wilhoit <48036388+DefSecSentinel@users.noreply.github.com>
This commit is contained in:
Ruben Groenewoud
2026-01-08 11:10:46 +01:00
committed by GitHub
parent ccd3f70ee8
commit e1698890a4
41 changed files with 1121 additions and 1017 deletions
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rules/linux/execution_shell_via_suspicious_binary.toml
+64 -66
View File
@@ -2,7 +2,7 @@
creation_date = "2023/07/05"
integration = ["endpoint"]
maturity = "production"
updated_date = "2025/02/04"
updated_date = "2025/12/19"
[rule]
author = ["Elastic"]
@@ -17,67 +17,6 @@ index = ["logs-endpoint.events.network*", "logs-endpoint.events.process*"]
language = "eql"
license = "Elastic License v2"
name = "Potential Reverse Shell via Suspicious Binary"
references = [
"https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/Methodology%20and%20Resources/Reverse%20Shell%20Cheatsheet.md",
]
risk_score = 47
rule_id = "fa3a59dc-33c3-43bf-80a9-e8437a922c7f"
setup = """## Setup
This rule requires data coming in from Elastic Defend.
### Elastic Defend Integration Setup
Elastic Defend is integrated into the Elastic Agent using Fleet. Upon configuration, the integration allows the Elastic Agent to monitor events on your host and send data to the Elastic Security app.
#### Prerequisite Requirements:
- Fleet is required for Elastic Defend.
- To configure Fleet Server refer to the [documentation](https://www.elastic.co/guide/en/fleet/current/fleet-server.html).
#### The following steps should be executed in order to add the Elastic Defend integration on a Linux System:
- Go to the Kibana home page and click "Add integrations".
- In the query bar, search for "Elastic Defend" and select the integration to see more details about it.
- Click "Add Elastic Defend".
- Configure the integration name and optionally add a description.
- Select the type of environment you want to protect, either "Traditional Endpoints" or "Cloud Workloads".
- Select a configuration preset. Each preset comes with different default settings for Elastic Agent, you can further customize these later by configuring the Elastic Defend integration policy. [Helper guide](https://www.elastic.co/guide/en/security/current/configure-endpoint-integration-policy.html).
- We suggest selecting "Complete EDR (Endpoint Detection and Response)" as a configuration setting, that provides "All events; all preventions"
- Enter a name for the agent policy in "New agent policy name". If other agent policies already exist, you can click the "Existing hosts" tab and select an existing policy instead.
For more details on Elastic Agent configuration settings, refer to the [helper guide](https://www.elastic.co/guide/en/fleet/8.10/agent-policy.html).
- Click "Save and Continue".
- To complete the integration, select "Add Elastic Agent to your hosts" and continue to the next section to install the Elastic Agent on your hosts.
For more details on Elastic Defend refer to the [helper guide](https://www.elastic.co/guide/en/security/current/install-endpoint.html).
"""
severity = "medium"
tags = [
"Domain: Endpoint",
"OS: Linux",
"Use Case: Threat Detection",
"Tactic: Execution",
"Data Source: Elastic Defend",
"Resources: Investigation Guide",
]
type = "eql"
query = '''
sequence by host.id, process.entity_id with maxspan=1s
[ process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.executable : (
"./*", "/tmp/*", "/var/tmp/*", "/var/www/*", "/dev/shm/*", "/etc/init.d/*", "/etc/rc*.d/*",
"/etc/crontab", "/etc/cron.*", "/etc/update-motd.d/*", "/usr/lib/update-notifier/*",
"/boot/*", "/srv/*", "/run/*", "/root/*", "/etc/rc.local"
) and
process.parent.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and not
process.name : ("curl", "wget", "ping", "apt", "dpkg", "yum", "rpm", "dnf", "dockerd") ]
[ network where host.os.type == "linux" and event.type == "start" and event.action in ("connection_attempted", "connection_accepted") and
process.executable : (
"./*", "/tmp/*", "/var/tmp/*", "/var/www/*", "/dev/shm/*", "/etc/init.d/*", "/etc/rc*.d/*",
"/etc/crontab", "/etc/cron.*", "/etc/update-motd.d/*", "/usr/lib/update-notifier/*",
"/boot/*", "/srv/*", "/run/*", "/root/*", "/etc/rc.local"
) and destination.ip != null and destination.ip != "127.0.0.1" and destination.ip != "::1" ]
[ process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and
process.parent.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") ]
'''
note = """## Triage and analysis
> **Disclaimer**:
@@ -113,35 +52,94 @@ Reverse shells are a common technique used by attackers to gain persistent acces
- Restore the affected system from a known good backup to ensure that any malicious changes are reverted.
- Update and patch the system to the latest security standards to close any vulnerabilities that may have been exploited.
- Escalate the incident to the security operations team for further investigation and to assess the potential impact on other systems within the network."""
references = [
"https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/Methodology%20and%20Resources/Reverse%20Shell%20Cheatsheet.md",
]
risk_score = 73
rule_id = "fa3a59dc-33c3-43bf-80a9-e8437a922c7f"
setup = """## Setup
This rule requires data coming in from Elastic Defend.
### Elastic Defend Integration Setup
Elastic Defend is integrated into the Elastic Agent using Fleet. Upon configuration, the integration allows the Elastic Agent to monitor events on your host and send data to the Elastic Security app.
#### Prerequisite Requirements:
- Fleet is required for Elastic Defend.
- To configure Fleet Server refer to the [documentation](https://www.elastic.co/guide/en/fleet/current/fleet-server.html).
#### The following steps should be executed in order to add the Elastic Defend integration on a Linux System:
- Go to the Kibana home page and click "Add integrations".
- In the query bar, search for "Elastic Defend" and select the integration to see more details about it.
- Click "Add Elastic Defend".
- Configure the integration name and optionally add a description.
- Select the type of environment you want to protect, either "Traditional Endpoints" or "Cloud Workloads".
- Select a configuration preset. Each preset comes with different default settings for Elastic Agent, you can further customize these later by configuring the Elastic Defend integration policy. [Helper guide](https://www.elastic.co/guide/en/security/current/configure-endpoint-integration-policy.html).
- We suggest selecting "Complete EDR (Endpoint Detection and Response)" as a configuration setting, that provides "All events; all preventions"
- Enter a name for the agent policy in "New agent policy name". If other agent policies already exist, you can click the "Existing hosts" tab and select an existing policy instead.
For more details on Elastic Agent configuration settings, refer to the [helper guide](https://www.elastic.co/guide/en/fleet/8.10/agent-policy.html).
- Click "Save and Continue".
- To complete the integration, select "Add Elastic Agent to your hosts" and continue to the next section to install the Elastic Agent on your hosts.
For more details on Elastic Defend refer to the [helper guide](https://www.elastic.co/guide/en/security/current/install-endpoint.html).
"""
severity = "high"
tags = [
"Domain: Endpoint",
"OS: Linux",
"Use Case: Threat Detection",
"Tactic: Execution",
"Data Source: Elastic Defend",
"Resources: Investigation Guide",
]
type = "eql"
query = '''
sequence by host.id, process.entity_id with maxspan=1s
[ process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.executable : (
"./*", "/tmp/*", "/var/tmp/*", "/var/www/*", "/dev/shm/*", "/etc/init.d/*", "/etc/rc*.d/*",
"/etc/crontab", "/etc/cron.*", "/etc/update-motd.d/*", "/usr/lib/update-notifier/*",
"/boot/*", "/srv/*", "/run/*", "/root/*", "/etc/rc.local"
) and
process.parent.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and not
process.name : ("curl", "wget", "ping", "apt", "dpkg", "yum", "rpm", "dnf", "dockerd") ]
[ network where host.os.type == "linux" and event.type == "start" and event.action in ("connection_attempted", "connection_accepted") and
process.executable : (
"./*", "/tmp/*", "/var/tmp/*", "/var/www/*", "/dev/shm/*", "/etc/init.d/*", "/etc/rc*.d/*",
"/etc/crontab", "/etc/cron.*", "/etc/update-motd.d/*", "/usr/lib/update-notifier/*",
"/boot/*", "/srv/*", "/run/*", "/root/*", "/etc/rc.local"
) and destination.ip != null and destination.ip != "127.0.0.1" and destination.ip != "::1" ]
[ process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and
process.parent.name : ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") ]
'''
[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"
[[rule.threat.technique.subtechnique]]
id = "T1059.004"
name = "Unix Shell"
reference = "https://attack.mitre.org/techniques/T1059/004/"
[rule.threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1071"
name = "Application Layer Protocol"
reference = "https://attack.mitre.org/techniques/T1071/"
[rule.threat.tactic]
id = "TA0011"
name = "Command and Control"
reference = "https://attack.mitre.org/tactics/TA0011/"