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cis-ubuntu1604-v200-5-3-1

DevOps & Security
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Ensure permissions on /etc/ssh/sshd_config are configured

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_16.04_LTS_Benchmark_v2.0.0/cis-ubuntu1604-v200-5-3-1/SKILL.md

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CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 5.3.1

Description

The /etc/ssh/sshd_config file contains configuration specifications for sshd. The command below sets the owner and group of the file to root.

Rationale

The /etc/ssh/sshd_config file needs to be protected from unauthorized changes by non-privileged users.

Audit Procedure

Command Line

Run the following command and verify Uid and Gid are both 0/root and Access does not grant permissions to group or other:

stat /etc/ssh/sshd_config

Expected Result

Access: (0600/-rw-------)  Uid: (    0/    root)  Gid: (    0/    root)

Remediation

Command Line

Run the following commands to set ownership and permissions on /etc/ssh/sshd_config:

chown root:root /etc/ssh/sshd_config
chmod og-rwx /etc/ssh/sshd_config

Default Value

Access: (0600/-rw-------) Uid: ( 0/ root) Gid: ( 0/ root)

References

  1. SSHD_CONFIG(5)

CIS Controls

Version 7

14.6 Protect Information through Access Control Lists - Protect all information stored on systems with file system, network share, claims, application, or database specific access control lists. These controls will enforce the principle that only authorized individuals should have access to the information based on their need to access the information as a part of their responsibilities.

Profile Applicability

  • Level 1 - Server
  • Level 1 - Workstation

Assessment Status

Automated