cis-gcp-cos-2.1.4

DevOps & Security

Ensure rsync service is not enabled

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Cloud_Providers/Google_Cloud_Platform/CIS_Google_Container-Optimized_OS_Benchmark_v1.2.0/cis-gcp-cos-2.1.4/SKILL.md

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2.1.4 Ensure rsync service is not enabled (Automated)

Description

The rsyncd service can be used to synchronize files between systems over network links.

Rationale

The rsyncd service presents a security risk as it uses unencrypted protocols for communication.

Audit Procedure

Run the following command to verify rsyncd is not enabled:

# systemctl is-enabled rsyncd
disabled

Verify result is not "enabled".

Expected Result

The command should return disabled, confirming that the rsync service is not enabled.

Remediation

Run the following command to disable rsyncd:

# systemctl --now disable rsyncd

/etc is stateless on Container-Optimized OS. Therefore, the steps mentioned above needs to be performed after every boot.

Additional Information:

Additional methods of disabling a service exist. Consult your distribution documentation for appropriate methods.

On some distributions the rsync service is known as rsync, not rsyncd.

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	4.4 Implement and Manage a Firewall on Servers - Implement and manage a firewall on servers, where supported. Example implementations include a virtual firewall, operating system firewall, or a third-party firewall agent.	X	X	X
v8	4.5 Implement and Manage a Firewall on End-User Devices - Implement and manage a host-based firewall or port-filtering tool on end-user devices, with a default-deny rule that drops all traffic except those services and ports that are explicitly allowed.	X	X	X
v8	4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software - Uninstall or disable unnecessary services on enterprise assets and software, such as an unused file sharing service, web application module, or service function.		X	X
v7	9.2 Ensure Only Approved Ports, Protocols and Services Are Running - Ensure that only network ports, protocols, and services listening on a system with validated business needs, are running on each system.		X	X

Profile

Level 1 - Server