# Cis Bind9 V301 2 2

> Cis Bind9 V301 2 2 is an Agent Skill for devops & security published in the CyberStrikeus/CyberStrike repository on GitHub: a SKILL.md instruction file an AI agent can load to do this task.

Give the BIND User Account an Invalid Shell (Automated)

- Skill name: `cis-bind9-v301-2-2`
- Category: [DevOps & Security](https://www.openparable.com/skill/devops-security/1)
- Source: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Server_Software/Bind/CIS_ISC_BIND_DNS_Server_9.9_Benchmark_v3.0.1/cis-bind9-v301-2-2/SKILL.md
- Repository: CyberStrikeus/CyberStrike (1,211 GitHub stars when collected)

## SKILL.md

# CIS 2.2 — Give the BIND User Account an Invalid Shell

## Profile Applicability

- Level 1 - Authoritative Name Server
- Level 1 - Caching Only Name Server

## Description

The BIND user account, named by default, must not be used as a regular login account, and should be assigned an invalid or `nologin` shell to ensure that the account cannot be used to login.

## Rationale

Service accounts such as the `named` account represent a risk if they can be used to get a login shell to the system.

## Impact

Not Applicable

## Audit Procedure

Check the `named` login shell in the `/etc/passwd` file:

```bash
# grep named /etc/passwd
named:x:25:25:Named:/var/named:/sbin/nologin
```

The named account shell must be `/sbin/nologin` or `/dev/null` similar to the entry shown.

## Remediation

Change the named account to use the `nologin` shell as shown:

```bash
# chsh -s /sbin/nologin named
```

## Default Value

/sbin/nologin

## References

Not Applicable

## CIS Controls

| Controls Version | Control                             | IG 1 | IG 2 | IG 3 |
| ---------------- | ----------------------------------- | ---- | ---- | ---- |
| v6               | 16 - Account Monitoring and Control | N    | Y    | Y    |

## MITRE ATT&CK Mappings

| Tactic               | Technique              |
| -------------------- | ---------------------- |
| Privilege Escalation | T1078 - Valid Accounts |
| Persistence          | T1136 - Create Account |

## Profile

- Level 1 - Authoritative Name Server
- Level 1 - Caching Only Name Server

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Source: https://www.openparable.com/skill/devops-security/cis-bind9-v301-2-2 (OpenParable). Cite the canonical URL above.