| name | cis-ubuntu1604-v200-4-1-4 |
| description | Ensure events that modify user/group information are collected |
| category | cis-logging |
| version | 2.0.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","linux","ubuntu-16.04","auditd","logging"] |
| cis_id | 4.1.4 |
| cis_benchmark | CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 4.1.4
Profile
- Level: 2 - Server
- Level: 2 - Workstation
- Assessment Status: Automated
Description
Record events affecting the group, passwd (user IDs), shadow and gshadow (passwords) or /etc/security/opasswd (old passwords, based on remember parameter in the PAM configuration) files. The parameters in this section will watch the files to see if they have been opened for write or have had attribute changes (e.g. permissions) and tag them with the identifier "identity" in the audit log file.
Note: Reloading the auditd config to set active settings requires the auditd service to be restarted, and may require a system reboot.
Rationale
Unexpected changes to these files could be an indication that the system has been compromised and that an unauthorized user is attempting to hide their activities or compromise additional accounts.
Impact
None.
Audit Procedure
Command Line
Run the following command to verify the rules are contained in a .rules file in the /etc/audit/rules.d/ directory:
grep identity /etc/audit/rules.d/*.rules
Verify the output matches:
-w /etc/group -p wa -k identity
-w /etc/passwd -p wa -k identity
-w /etc/gshadow -p wa -k identity
-w /etc/shadow -p wa -k identity
-w /etc/security/opasswd -p wa -k identity
Run the following command to verify that rules are in the running auditd config:
auditctl -l | grep identity
Verify the output matches:
-w /etc/group -p wa -k identity
-w /etc/passwd -p wa -k identity
-w /etc/gshadow -p wa -k identity
-w /etc/shadow -p wa -k identity
-w /etc/security/opasswd -p wa -k identity
Expected Result
Output should match the rules listed above.
Remediation
Command Line
Edit or create a file in the /etc/audit/rules.d/ directory ending in .rules.
Example: vi /etc/audit/rules.d/50-identity.rules
Add the following lines:
-w /etc/group -p wa -k identity
-w /etc/passwd -p wa -k identity
-w /etc/gshadow -p wa -k identity
-w /etc/shadow -p wa -k identity
-w /etc/security/opasswd -p wa -k identity
Default Value
By default, no audit rules are configured for identity file changes.
