# Cis Ubuntu1604 V200 3 5 2 4

> Ensure a nftables table exists

- Skill: `cyberstrikeus/cis-ubuntu1604-v200-3-5-2-4` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu1604-v200-3-5-2-4`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-ubuntu1604-v200-3-5-2-4/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/cis-ubuntu1604-v200-3-5-2-4

---


# CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - Control 3.5.2.4

## Profile

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

## Description

Tables hold chains. Each table only has one address family and only applies to packets of this family. Tables can have one of five families.

## Rationale

nftables doesn't have any default tables. Without a table being build, nftables will not filter network traffic.

## Impact

Adding rules to a running nftables can cause loss of connectivity to the system.

## Audit Procedure

### Command Line

Run the following command to verify that a nftables table exists:

```bash
nft list tables
```

## Expected Result

Return should include a list of nftables.

Example:

```
table inet filter
```

## Remediation

### Command Line

Run the following command to create a table in nftables:

```bash
nft create table inet <table name>
```

Example:

```bash
nft create table inet filter
```

## References

None

## CIS Controls

Version 7

9.4 Apply Host-based Firewalls or Port Filtering - Apply host-based firewalls or port filtering tools on end systems, with a default-deny rule that drops all traffic except those services and ports that are explicitly allowed.