8.8
CWE
77 78
Advisory Published
Updated

CVE-2023-34139: Command Injection

First published: Mon Jul 17 2023(Updated: )

A command injection vulnerability in the Free Time WiFi hotspot feature of the Zyxel USG FLEX series firmware versions 4.50 through 5.36 Patch 2 and VPN series firmware versions 4.20 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands on an affected device.

Credit: security@zyxel.com.tw security@zyxel.com.tw

Affected SoftwareAffected VersionHow to fix
Zyxel Usg 2200-vpn Firmware>=4.20<5.37
Zyxel Usg 2200-vpn
Zyxel Usg Flex 100 Firmware>=4.50<5.37
Zyxel Usg Flex 100
Zyxel Usg Flex 100w Firmware>=4.50<5.37
Zyxel Usg Flex 100w
Zyxel Usg Flex 200 Firmware>=4.50<5.37
Zyxel Usg Flex 200
Zyxel Usg Flex 50 Firmware>=4.50<5.37
Zyxel Usg Flex 50
Zyxel Usg Flex 500 Firmware>=4.50<5.37
Zyxel Usg Flex 500
Zyxel Usg Flex 50w Firmware>=4.50<5.37
Zyxel Usg Flex 50w
Zyxel Usg Flex 700 Firmware>=4.50<5.37
Zyxel Usg Flex 700
Zyxel Zywall Vpn100 Firmware>=4.20<5.37
Zyxel Zywall Vpn100
Zyxel Zywall Vpn2s Firmware>=4.20<5.37
Zyxel Zywall Vpn2s
Zyxel Zywall Vpn300 Firmware>=4.20<5.37
Zyxel Zywall Vpn300
Zyxel Zywall Vpn50 Firmware>=4.20<5.37
Zyxel Zywall Vpn50
Zyxel Zywall Vpn 100 Firmware>=4.20<5.37
Zyxel Zywall Vpn 100
Zyxel Zywall Vpn 300 Firmware>=4.20<5.37
Zyxel Zywall Vpn 300
Zyxel Zywall Vpn 50 Firmware>=4.20<5.37
Zyxel Zywall Vpn 50

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Frequently Asked Questions

  • What is the vulnerability ID?

    The vulnerability ID is CVE-2023-34139.

  • What is the severity of CVE-2023-34139?

    The severity of CVE-2023-34139 is high.

  • Which Zyxel products are affected by CVE-2023-34139?

    Zyxel USG FLEX series firmware versions 4.50 through 5.36 Patch 2 and VPN series firmware versions 4.20 through 5.36 Patch 2 are affected.

  • How can an attacker exploit CVE-2023-34139?

    An unauthenticated, LAN-based attacker can exploit CVE-2023-34139 by executing OS commands on an affected device.

  • Is there a fix for CVE-2023-34139?

    Yes, users are advised to upgrade their firmware to version 5.37 or above to mitigate the vulnerability.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2025 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203