Cis Ubuntu1804 V220 5 1 2 7

---
name: cis-ubuntu1804-v220-5-1-2-7
description: "Ensure rsyslog is not configured to receive logs from a remote client"
category: cis-logging
version: "2.2.0"
author: cyberstrike-official
tags: [cis, ubuntu, linux, ubuntu-18.04, rsyslog, logging]
cis_id: "5.1.2.7"
cis_benchmark: "CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0"
tech_stack: [ubuntu, linux]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# 5.1.2.7 Ensure rsyslog is not configured to receive logs from a remote client (Automated)

## Profile

- **Level:** 1 - Server
- **Level:** 1 - Workstation
- **Assessment Status:** Automated

## Description

RSyslog supports the ability to receive messages from remote hosts, thus acting as a log server. Clients should not receive data from other hosts.

## Rationale

If a client is configured to also receive data, thus turning it into a server, the client system is acting outside it's operational boundary.

## Audit Procedure

### Command Line

Review the `/etc/rsyslog.conf` and `/etc/rsyslog.d/*.conf` files and verify that the system is not configured to accept incoming logs.

Old format:

```bash
grep '$ModLoad imtcp' /etc/rsyslog.conf /etc/rsyslog.d/*.conf
grep '$InputTCPServerRun' /etc/rsyslog.conf /etc/rsyslog.d/*.conf
```

No output expected.

New format:

```bash
grep -P -- '^\h*module\(load="imtcp"\)' /etc/rsyslog.conf /etc/rsyslog.d/*.conf
grep -P -- '^\h*input\(type="imtcp" port="514"\)' /etc/rsyslog.conf /etc/rsyslog.d/*.conf
```

No output expected.

## Expected Result

No output should be returned for any of the commands.

## Remediation

### Command Line

Remove or comment out any lines in `/etc/rsyslog.conf` and `/etc/rsyslog.d/*.conf` that configure rsyslog to accept incoming logs. Restart the service:

```bash
systemctl restart rsyslog
```

## Default Value

rsyslog is not configured to receive logs from remote clients by default.

## References

1. NIST SP 800-53 Rev. 5: AU-2, AU-12, CM-6, CM-7

## CIS Controls

| Controls Version | Control                                                                                                                                                                                                       |
| ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| v8               | 4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software - Uninstall or disable unnecessary services on enterprise assets and software.                                                |
| v8               | 8.2 Collect Audit Logs - Collect audit logs. Ensure that logging, per the enterprise's audit log management process, has been enabled across enterprise assets.                                               |
| v7               | 6.2 Activate audit logging - Ensure that local logging has been enabled on all systems and networking devices.                                                                                                |
| v7               | 6.3 Enable Detailed Logging - Enable system logging to include detailed information such as an event source, date, user, timestamp, source addresses, destination addresses, and other useful elements.       |
| 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. |