Files
sigma-rules/rules/linux/execution_shell_suspicious_parent_child_revshell_linux.toml
T
Ruben Groenewoud 020fff3aea [Rule Tuning] Linux Rules (#3092)
* [Rule Tuning] [WIP] Linux DR

* Update defense_evasion_binary_copied_to_suspicious_directory.toml

* Fixed tag

* Added additional tuning

* unit test fix

* Additional tuning

* tuning

* added max signals

* Added max_signals=1 to brute force rules

* Cross-Platform Tuning

* Small fix

* new_terms conversion

* typo

* new_terms conversion

* Ransomware rule tuning

* performance tuning

* new_terms conversion for auditd_manager

* tune

* Need coffee

* kql/eql stuff

* formatting improvement

* new_terms sudo hijacking conversion

* exclusion

* Deprecations that were added last tuning

* Deprecations that were added last tuning

* Increased max timespan for brute force rules

* version bump

* added domain tag

* Two tunings

* More tuning

* Additional tuning

* updated_date bump

* query optimization

* Tuning

* Readded the exclusions for this one

* Changed int comparison

* Some tunings

* Update persistence_systemd_scheduled_timer_created.toml

* Update rules/linux/privilege_escalation_ld_preload_shared_object_modif.toml

Co-authored-by: Isai <59296946+imays11@users.noreply.github.com>

* [New Rule] Potential curl CVE-2023-38545 Exploitation

* Revert "[New Rule] Potential curl CVE-2023-38545 Exploitation"

This reverts commit 9c04d1b53d3d63678289f43ec0c7b617d26f1ce0.

* Update rules/cross-platform/command_and_control_non_standard_ssh_port.toml

* Update rules/linux/command_and_control_cat_network_activity.toml

* Update persistence_message_of_the_day_execution.toml

* Changed max_signals

* Revert "Merge branch 'main' into rule-tuning-ongoing-dr"

This reverts commit 1106b5d2eba1a3529eff325226d6baabfd4b0bf3, reversing
changes made to 5ff510757f25b0cb32e1ef18e9e2c34c8ec325a8.

* Revertable merge

* Update defense_evasion_ld_preload_env_variable_process_injection.toml

* File name change

---------

Co-authored-by: Isai <59296946+imays11@users.noreply.github.com>
Co-authored-by: Jonhnathan <26856693+w0rk3r@users.noreply.github.com>
2023-10-23 16:28:58 +02:00

104 lines
5.2 KiB
TOML

[metadata]
creation_date = "2023/07/04"
integration = ["endpoint"]
maturity = "production"
min_stack_comments = "New fields added: required_fields, related_integrations, setup"
min_stack_version = "8.3.0"
updated_date = "2023/10/16"
[rule]
author = ["Elastic"]
description = """
This detection rule detects the creation of a shell through a suspicious parent child relationship. Any reverse shells
spawned by the specified utilities that use a forked process to initialize the connection attempt will be captured
through this rule. Attackers may spawn reverse shells to establish persistence onto a target system.
"""
from = "now-9m"
index = ["logs-endpoint.events.*"]
language = "eql"
license = "Elastic License v2"
name = "Deprecated - Potential Reverse Shell via Suspicious Parent Process"
note = "This rule was deprecated due to its addition to the umbrella `Potential Reverse Shell via Suspicious Child Process` (76e4d92b-61c1-4a95-ab61-5fd94179a1ee) rule."
references = [
"https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/Methodology%20and%20Resources/Reverse%20Shell%20Cheatsheet.md"
]
risk_score = 47
rule_id = "4b1a807a-4e7b-414e-8cea-24bf580f6fc5"
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 to select "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"]
type = "eql"
query = '''
sequence by host.id, process.parent.entity_id with maxspan=1s
[ process where host.os.type == "linux" and event.type == "start" and event.action == "fork" and (
(process.name : "python*" and process.args == "-c" and not process.args == "/usr/bin/supervisord") or
(process.name : "php*" and process.args == "-r") or
(process.name : "perl" and process.args == "-e") or
(process.name : "ruby" and process.args in ("-e", "-rsocket")) or
(process.name : "lua*" and process.args == "-e") or
(process.name : "openssl" and process.args : "-connect") or
(process.name : ("nc", "ncat", "netcat") and process.args_count >= 3 and not process.args == "-z") or
(process.name : "telnet" and process.args_count >= 3) or
(process.name : "awk")) and
process.parent.name : ("python*", "php*", "perl", "ruby", "lua*", "openssl", "nc", "netcat", "ncat", "telnet", "awk") ]
[ network where host.os.type == "linux" and event.type == "start" and event.action in ("connection_attempted", "connection_accepted") and
process.name : ("python*", "php*", "perl", "ruby", "lua*", "openssl", "nc", "netcat", "ncat", "telnet", "awk") and
destination.ip != null and destination.ip != "127.0.0.1" and destination.ip != "::1" ]
'''
[[rule.threat]]
framework = "MITRE ATT&CK"
[rule.threat.tactic]
name = "Execution"
id = "TA0002"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[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]]
framework = "MITRE ATT&CK"
[rule.threat.tactic]
name = "Command and Control"
id = "TA0011"
reference = "https://attack.mitre.org/tactics/TA0011/"
[[rule.threat.technique]]
name = "Application Layer Protocol"
id = "T1071"
reference = "https://attack.mitre.org/techniques/T1071/"