---
title: "HOST-SSH-009 SSH Host Private Keys Readable by Others"
canonical: https://openvapt.com/checks/HOST-SSH-009.html
html: https://openvapt.com/checks/HOST-SSH-009.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-SSH-009 SSH Host Private Keys Readable by Others

Checks that SSH host private keys are readable only by root.

- Domain: Server
- Severity: High
- Control category: Cryptography and TLS
- Fix effort: low
- CVSS v3.1 vector: `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`
- CIS Controls v8: 3.10
- NIST CSF 2.0: PR.DS-02
- CWE: CWE-732
- NIST SP 800-53 Rev. 5: AC-3, AC-6

## Why It Matters

Anyone who can read a host private key can impersonate the server and intercept SSH sessions from users who trust it.

## How It Detects

Stats every existing file matching /etc/ssh/ssh_host_*_key (metadata only, contents are never read) and fails if it is readable or writable by others.

## How to Fix

chown root:root /etc/ssh/ssh_host_*_key && chmod 600 /etc/ssh/ssh_host_*_key  (0640 with group ssh_keys is acceptable on RHEL family).

## How to Verify

```
stat -c '%a %U:%G %n' /etc/ssh/ssh_host_*_key
```

## Learn the Theory

- [P2 SSH Security](https://openvapt.com/academy/p2.md)

## References

- [OpenBSD, sshd_config(5) manual page](https://man.openbsd.org/sshd_config)

## Source Code

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

Run it: `openvapt scan --only HOST-SSH-009`. Read it offline: `openvapt explain HOST-SSH-009`.

---

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