---
title: "HOST-FS-002 Temporary Directory Missing the Sticky Bit"
canonical: https://openvapt.com/checks/HOST-FS-002.html
html: https://openvapt.com/checks/HOST-FS-002.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-002 Temporary Directory Missing the Sticky Bit

Checks that world-writable temp directories have the sticky bit set.

- Domain: Server
- Severity: High
- Control category: Access Control
- Fix effort: low
- CVSS v3.1 vector: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`
- CIS Controls v8: 3.3
- NIST CSF 2.0: PR.AA-05, PR.DS-01
- CWE: CWE-377, CWE-732
- NIST SP 800-53 Rev. 5: AC-3
- Benchmark topic: Filesystem: sticky bit on world-writable directories (topic only, no benchmark text)

## Why It Matters

Without the sticky bit any user can delete or replace other users' files in /tmp, enabling symlink attacks against root-run scripts.

## How It Detects

Stats /tmp and /var/tmp; world-writable without the sticky bit (mode 1777 expected) fails.

## How to Fix

chmod 1777 /tmp /var/tmp

## How to Verify

```
stat -c '%a %n' /tmp /var/tmp  should print 1777 for both.
```

## Learn the Theory

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

## References

- [chmod(1), Linux man-pages (restricted deletion flag)](https://man7.org/linux/man-pages/man1/chmod.1.html)

## Source Code

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

Run it: `openvapt scan --only HOST-FS-002`. Read it offline: `openvapt explain HOST-FS-002`.

---

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