Sensitive Files Compression

Identifies the use of a compression utility to collect known files containing sensitive information, such as credentials and system configurations.

Rule type: new_terms

Rule indices:

auditbeat-*
logs-endpoint.events.*
endgame-*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

https://www.trendmicro.com/en_ca/research/20/l/teamtnt-now-deploying-ddos-capable-irc-bot-tntbotinger.html

Tags:

Domain: Endpoint
OS: Linux
Use Case: Threat Detection
Tactic: Collection
Tactic: Credential Access
Data Source: Elastic Endgame
Data Source: Elastic Defend

Version: 208

Rule authors:

Elastic

Rule license: Elastic License v2

Setup

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Setup

This rule requires data coming in from one of the following integrations: - Elastic Defend - Auditbeat

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.

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.
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.
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.

Auditbeat Setup

Auditbeat is a lightweight shipper that you can install on your servers to audit the activities of users and processes on your systems. For example, you can use Auditbeat to collect and centralize audit events from the Linux Audit Framework. You can also use Auditbeat to detect changes to critical files, like binaries and configuration files, and identify potential security policy violations.

The following steps should be executed in order to add the Auditbeat on a Linux System:

Elastic provides repositories available for APT and YUM-based distributions. Note that we provide binary packages, but no source packages.
To install the APT and YUM repositories follow the setup instructions in this helper guide.
To run Auditbeat on Docker follow the setup instructions in the helper guide.
To run Auditbeat on Kubernetes follow the setup instructions in the helper guide.
For complete “Setup and Run Auditbeat” information refer to the helper guide.

Rule query

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event.category:process and host.os.type:linux and event.type:start and
  process.name:(zip or tar or gzip or hdiutil or 7z) and
  process.args:
    (
      /root/.ssh/id_rsa or
      /root/.ssh/id_rsa.pub or
      /root/.ssh/id_ed25519 or
      /root/.ssh/id_ed25519.pub or
      /root/.ssh/authorized_keys or
      /root/.ssh/authorized_keys2 or
      /root/.ssh/known_hosts or
      /root/.bash_history or
      /etc/hosts or
      /home/*/.ssh/id_rsa or
      /home/*/.ssh/id_rsa.pub or
      /home/*/.ssh/id_ed25519 or
      /home/*/.ssh/id_ed25519.pub or
      /home/*/.ssh/authorized_keys or
      /home/*/.ssh/authorized_keys2 or
      /home/*/.ssh/known_hosts or
      /home/*/.bash_history or
      /root/.aws/credentials or
      /root/.aws/config or
      /home/*/.aws/credentials or
      /home/*/.aws/config or
      /root/.docker/config.json or
      /home/*/.docker/config.json or
      /etc/group or
      /etc/passwd or
      /etc/shadow or
      /etc/gshadow
    )

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Credential Access
- ID: TA0006
- Reference URL: https://attack.mitre.org/tactics/TA0006/
Technique:
- Name: Unsecured Credentials
- ID: T1552
- Reference URL: https://attack.mitre.org/techniques/T1552/
Sub-technique:
- Name: Credentials In Files
- ID: T1552.001
- Reference URL: https://attack.mitre.org/techniques/T1552/001/
Tactic:
- Name: Collection
- ID: TA0009
- Reference URL: https://attack.mitre.org/tactics/TA0009/
Technique:
- Name: Archive Collected Data
- ID: T1560
- Reference URL: https://attack.mitre.org/techniques/T1560/
Sub-technique:
- Name: Archive via Utility
- ID: T1560.001
- Reference URL: https://attack.mitre.org/techniques/T1560/001/

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