CWE
79
Advisory Published
Updated

CVE-2023-27990: XSS

First published: Mon Apr 24 2023(Updated: )

The cross-site scripting (XSS) vulnerability in Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow an authenticated attacker with administrator privileges to store malicious scripts in a vulnerable device. A successful XSS attack could then result in the stored malicious scripts being executed when the user visits the Logs page of the GUI on the device.

Credit: security@zyxel.com.tw

Affected SoftwareAffected VersionHow to fix
Zyxel ATP200 firmware>=4.32<5.36
Zyxel Zywall ATP200
Zyxel ZyWall ATP100 Firmware>=4.32<5.36
Zyxel ATP100 Firmware
Zyxel Zywall ATP700>=4.32<5.36
Zyxel ATP700 Firmware
Zyxel ATP500 Firmware>=4.32<5.36
Zyxel ATP500 Firmware
Zyxel ATP100W Firmware>=4.32<5.36
Zyxel ATP100W Firmware
Zyxel Zywall ATP800 Firmware>=4.32<5.36
Zyxel Zywall ATP800 Firmware
Zyxel USG Flex 100 firmware>=4.50<5.36
Zyxel USG Flex 100 firmware
Zyxel USG FLEX 50(W) series firmware>=4.50<5.36
Zyxel USG FLEX 50w
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 200 firmware
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 500 firmware
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 700 firmware
Zyxel USG FLEX 100w firmware>=4.50<5.36
Zyxel USG FLEX 100w firmware
Zyxel USG 20W-VPN Firmware>=4.16<5.36
Zyxel USG20
Zyxel USG FLEX 50w>=4.16<5.36
Zyxel USG FLEX 50(W) series firmware
Zyxel USG20W-VPN Firmware>=4.30<5.36
Zyxel USG20W-VPN Firmware
Zyxel VPN100>=4.30<5.36
Zyxel Zywall VPN100
Zyxel VPN1000 Firmware>=4.30<5.36
Zyxel VPN1000 Firmware
Zyxel Zywall VPN 300 Firmware>=4.30<5.36
Zyxel Zywall VPN300
Zyxel Zywall VPN 50 Firmware>=4.30<5.36
Zyxel VPN50 Firmware
All of
Zyxel ATP200 firmware>=4.32<5.36
Zyxel Zywall ATP200
All of
Zyxel ZyWall ATP100 Firmware>=4.32<5.36
Zyxel ATP100 Firmware
All of
Zyxel Zywall ATP700>=4.32<5.36
Zyxel ATP700 Firmware
All of
Zyxel ATP500 Firmware>=4.32<5.36
Zyxel ATP500 Firmware
All of
Zyxel ATP100W Firmware>=4.32<5.36
Zyxel ATP100W Firmware
All of
Zyxel Zywall ATP800 Firmware>=4.32<5.36
Zyxel Zywall ATP800 Firmware
All of
Zyxel USG Flex 100 firmware>=4.50<5.36
Zyxel USG Flex 100 firmware
All of
Zyxel USG FLEX 50(W) series firmware>=4.50<5.36
Zyxel USG FLEX 50w
All of
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 200 firmware
All of
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 500 firmware
All of
Zyxel USG FLEX firmware>=4.50<5.36
Zyxel USG FLEX 700 firmware
All of
Zyxel USG FLEX 100w firmware>=4.50<5.36
Zyxel USG FLEX 100w firmware
All of
Zyxel USG 20W-VPN Firmware>=4.16<5.36
Zyxel USG20
All of
Zyxel USG FLEX 50w>=4.16<5.36
Zyxel USG FLEX 50(W) series firmware
All of
Zyxel USG20W-VPN Firmware>=4.30<5.36
Zyxel USG20W-VPN Firmware
All of
Zyxel VPN100>=4.30<5.36
Zyxel Zywall VPN100
All of
Zyxel VPN1000 Firmware>=4.30<5.36
Zyxel VPN1000 Firmware
All of
Zyxel Zywall VPN 300 Firmware>=4.30<5.36
Zyxel Zywall VPN300
All of
Zyxel Zywall VPN 50 Firmware>=4.30<5.36
Zyxel VPN50 Firmware

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Frequently Asked Questions

  • What is the severity of CVE-2023-27990?

    The severity of CVE-2023-27990 is medium with a severity value of 4.8.

  • Which software versions are affected by CVE-2023-27990?

    CVE-2023-27990 affects Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35.

  • What is the Common Weakness Enumeration (CWE) of CVE-2023-27990?

    The Common Weakness Enumeration (CWE) of CVE-2023-27990 is CWE-79.

  • How can I fix CVE-2023-27990?

    To fix CVE-2023-27990, it is recommended to update to a firmware version that is not vulnerable. Refer to the vendor's security advisory for more information.

  • Where can I find more information about CVE-2023-27990?

    You can find more information about CVE-2023-27990 in the vendor's security advisory at https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls

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