---
title: "HOST-FS-003 World-Writable Files in System Configuration"
canonical: https://openvapt.com/checks/HOST-FS-003.html
html: https://openvapt.com/checks/HOST-FS-003.html
site: OpenVAPT, https://openvapt.com/
license: OpenVAPT Source-Available Licence 1.3, https://openvapt.com/legal/licence-text.html
modified: 2026-10-14
version: 0.1.0-alpha.6
---

# HOST-FS-003 World-Writable Files in System Configuration

Looks for files under /etc and in cron directories that any user can modify.

- Domain: Server
- Severity: High
- Control category: Access Control
- Fix effort: medium
- CVSS v3.1 vector: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`
- CIS Controls v8: 3.3
- NIST CSF 2.0: PR.AA-05, PR.DS-01
- CWE: CWE-732
- NIST SP 800-53 Rev. 5: AC-3, CM-6
- Benchmark topic: File permissions: no world-writable files (topic only, no benchmark text)

## Why It Matters

A world-writable config or cron file lets any local user change how a root-owned service behaves, often leading straight to root.

## How It Detects

Walks /etc (metadata only, up to 20000 files, symlinks not followed) and lists regular files with the 'other write' bit set, plus directories up to three levels deep that are world-writable without the sticky bit (anyone could replace files inside them).

## How to Fix

For each listed file or directory: chmod o-w <path>. Then find out how it became writable (a deployment script or a careless chmod 777).

## How to Verify

```
find /etc -xdev \( -type f -perm -0002 \) -o \( -type d -perm -0002 ! -perm -1000 \)  should print nothing.
```

## Learn the Theory

- [P1 Linux Server Hardening](https://openvapt.com/academy/p1.md)

## References

- [NIST SP 800-123, Guide to General Server Security](https://csrc.nist.gov/pubs/sp/800/123/final)

## Source Code

https://github.com/OpenVAPT/openvapt/blob/574f7f3333c44b75a3c649e2d93a76d507f75adf/internal/checks/host/files.go

Run it: `openvapt scan --only HOST-FS-003`. Read it offline: `openvapt explain HOST-FS-003`.

---

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