---
title: "HOST-USR-001 Extra Accounts With Root Privileges (UID 0)"
canonical: https://openvapt.com/checks/HOST-USR-001.html
html: https://openvapt.com/checks/HOST-USR-001.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-USR-001 Extra Accounts With Root Privileges (UID 0)

Checks /etc/passwd for accounts other than root that have user id 0.

- Domain: Server
- Severity: High
- Control category: Identity and Authentication
- 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: 5.4
- NIST CSF 2.0: PR.AA-05
- CWE: CWE-250, CWE-266
- NIST SP 800-53 Rev. 5: AC-2, AC-6
- Benchmark topic: User accounts: root is the only UID 0 account (topic only, no benchmark text)

## Why It Matters

Any account with UID 0 is root, whatever its name. Extra UID 0 accounts are a classic backdoor and bypass sudo logging.

## How It Detects

Reads /etc/passwd and lists every entry whose third field (UID) is 0, other than 'root'.

## How to Fix

Investigate who created each account. Remove it (userdel <name>) or give it a normal UID (usermod -u <new-uid> <name>). Grant admin rights through sudo instead.

## How to Verify

```
awk -F: '$3==0' /etc/passwd  should print only the root line.
```

## Learn the Theory

- [P7 Identity, Passwords and Privilege](https://openvapt.com/academy/p7.md)
- [P15 Access Control: Accounts, Sudo and Logins](https://openvapt.com/academy/p15.md)

## References

- [passwd(5), Linux man-pages](https://man7.org/linux/man-pages/man5/passwd.5.html)
- [NIST SP 800-53 Rev. 5, Security and Privacy Controls](https://csrc.nist.gov/pubs/sp/800/53/r5/upd1/final)

## Source Code

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

Run it: `openvapt scan --only HOST-USR-001`. Read it offline: `openvapt explain HOST-USR-001`.

---

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