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cis-ubuntu1804-v220-2-2-17

DevOps & Security
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Ensure rsync service is either not installed or is masked

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_18.04_LTS_Benchmark_v2.2.0/cis-ubuntu1804-v220-2-2-17/SKILL.md

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2.2.17 Ensure rsync service is either not installed or is masked (Automated)

Profile

  • Level 1 - Server
  • Level 1 - Workstation

Description

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

Rationale

The rsync service presents a security risk as the rsync protocol is unencrypted. The rsync package should be removed or if required for dependencies, the rsync service should be stopped and masked to reduce the attack area of the system.

Audit Procedure

Command Line

Run the following command to verify rsync is not installed:

# dpkg-query -s rsync &>/dev/null && echo "rsync is installed"

Nothing should be returned.

-- OR --

Run the following commands to verify that rsync is inactive and masked:

# systemctl is-active rsync
inactive

# systemctl is-enabled rsync
masked

Expected Result

Either rsync is not installed (no output), or rsync service is inactive and masked.

Remediation

Command Line

Run the following command to remove rsync:

# apt purge rsync

-- OR --

Run the following commands to stop and mask rsync:

# systemctl stop rsync
# systemctl mask rsync

References

  1. NIST SP 800-53 Rev. 5: CM-6, CM-7

CIS Controls

  • v8: 4.8 - Uninstall or Disable Unnecessary Services on Enterprise Assets and Software
  • v7: 9.2 - Ensure Only Approved Ports, Protocols and Services Are Running