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CIS Ubuntu 14.04 LTS - 2.1.3 Ensure discard services are not enabled

DevOps & Security
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Verify that discard inetd services are disabled to reduce attack surface

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How to use this skill

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_14.04_LTS_Benchmark_v2.1.0/cis-ubuntu1404-v210-2-1-3/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/cis-ubuntu-14-04-lts-2-1-3-ensure-discard-services-are-not-enabled/. Do not write files or run scripts until I approve.

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2.1.3 Ensure discard services are not enabled (Scored)

Profile Applicability

  • Level 1 - Server
  • Level 1 - Workstation

Description

discard is a network service that simply discards all data it receives. This service is intended for debugging and testing purposes. It is recommended that this service be disabled.

Rationale

Disabling this service will reduce the remote attack surface of the system.

Audit Procedure

Verify the discard service is not enabled. Run the following command and verify results are as indicated:

grep -R "^discard" /etc/inetd.*

No results should be returned.

Check /etc/xinetd.conf and /etc/xinetd.d/* and verify all discard services have disable = yes set.

Expected Result

No output should be returned from the grep command. All discard services in xinetd should have disable = yes.

Remediation

Comment out or remove any lines starting with discard from /etc/inetd.conf and /etc/inetd.d/*.

Set disable = yes on all discard services in /etc/xinetd.conf and /etc/xinetd.d/*.

Default Value

discard services are not enabled by default.

References

  • CIS Controls: 9.1 Limit Open Ports, Protocols, and Services

Profile

  • Level 1 - Server
  • Level 1 - Workstation