CIS 2.4 — Set root Ownership of BIND Directories

---
name: cis-bind9-v301-2-4-e772cdc9d7b7
description: "Set root Ownership of BIND Directories (Automated)"
category: cis-bind
version: "3.0.1"
author: cyberstrike-official
tags: [cis, bind, dns, isc-bind, bind9, permissions-ownership]
cis_id: "2.4"
cis_benchmark: "CIS ISC BIND DNS Server 9.9 Benchmark v3.0.1"
tech_stack: [bind, isc-bind, dns, linux]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# CIS 2.4 — Set root Ownership of BIND Directories

## Profile Applicability

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

## Description

All of the directories under which ISC BIND runs should be owned by root. Of course, any files created at run time by BIND will still be owned by named.

## Rationale

Restricting ownership of the directories provides defense in depth and will reduce the probability of unauthorized modifications to those resources. If there was a BIND vulnerability that allowed code execution as the named user, then the code would not be able to modify permissions on the BIND directories owned by root.

## Impact

Not Applicable

## Audit Procedure

Ensure that the variable `$BIND_HOME` is set to the directory under which BIND runs, typically the directory `/var/named/`. In the case of a `chroot`'ed configuration, the daemon will likely run under `/var/named/chroot/`, however the upper level directory of `/var/named/` should still be used as it is specific to the BIND service, and will include the `chroot` directory. Also, the variable `$RUNDIR` should be set to the directory which is used to create run-time files such as the `pid` file and session-key. Perform the following to ensure the directory ownership:

```bash
# find $BIND_HOME $RUNDIR type d \! -user root -ls
```

There should be NO directories listed in the output from the find command.

## Remediation

To correct the directory ownership, perform the following:

```bash
chown -R root $BIND_HOME $RUNDIR
```

## Default Value

The following directories are owned by `named` in the default RHEL7 package install:

- /var/named/dynamic
- /var/named/slaves
- /var/named/data
- /run/named

## References

Not Applicable

## CIS Controls

| Controls Version | Control                                              | IG 1 | IG 2 | IG 3 |
| ---------------- | ---------------------------------------------------- | ---- | ---- | ---- |
| v6               | 14.4 - Protect Information with Access Control Lists | Y    | Y    | Y    |

## MITRE ATT&CK Mappings

| Tactic          | Technique                                           |
| --------------- | --------------------------------------------------- |
| Defense Evasion | T1222 - File and Directory Permissions Modification |
| Persistence     | T1546 - Event Triggered Execution                   |

## Profile

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