CVE-2023-27990: XSS

Published 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.

Other sources

The 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.

Affected Software

76 affected components
Zyxel Atp200 Firmware>=4.32<5.36
Zyxel ATP200
Zyxel Atp100 Firmware>=4.32<5.36
Zyxel Atp100
Zyxel Atp700 Firmware>=4.32<5.36
Zyxel Atp700
Zyxel Atp500 Firmware>=4.32<5.36
Zyxel ATP500
Zyxel Atp100w Firmware>=4.32<5.36
Zyxel Atp100w
Zyxel Atp800 Firmware>=4.32<5.36
Zyxel ATP800
Zyxel Usg Flex 100 Firmware>=4.50<5.36
Zyxel Usg Flex 100
Zyxel Usg Flex 50 Firmware>=4.50<5.36
Zyxel USG FLEX 50
Zyxel USG FLEX 200 firmware>=4.50<5.36
Zyxel USG FLEX 200
Zyxel USG FLEX 500 firmware>=4.50<5.36
Zyxel USG FLEX 500
Zyxel USG FLEX 700 firmware>=4.50<5.36
Zyxel USG FLEX 700
Zyxel Usg Flex 100w Firmware>=4.50<5.36
Zyxel Usg Flex 100w
Zyxel Usg 20w-vpn Firmware>=4.16<5.36
Zyxel Usg 20w-vpn
Zyxel Usg Flex 50w Firmware>=4.16<5.36
Zyxel Usg Flex 50w
Zyxel Usg20-vpn Firmware>=4.30<5.36
Zyxel USG20-VPN
Zyxel Vpn100 Firmware>=4.30<5.36
Zyxel Vpn100
Zyxel Vpn1000 Firmware>=4.30<5.36
Zyxel Vpn1000
Zyxel Vpn300 Firmware>=4.30<5.36
Zyxel Vpn300
Zyxel Vpn50 Firmware>=4.30<5.36
Zyxel Vpn50
All of the following
Zyxel Atp200 Firmware>=4.32<5.36
Zyxel ATP200
All of the following
Zyxel Atp100 Firmware>=4.32<5.36
Zyxel Atp100
All of the following
Zyxel Atp700 Firmware>=4.32<5.36
Zyxel Atp700
All of the following
Zyxel Atp500 Firmware>=4.32<5.36
Zyxel ATP500
All of the following
Zyxel Atp100w Firmware>=4.32<5.36
Zyxel Atp100w
All of the following
Zyxel Atp800 Firmware>=4.32<5.36
Zyxel ATP800
All of the following
Zyxel Usg Flex 100 Firmware>=4.50<5.36
Zyxel Usg Flex 100
All of the following
Zyxel Usg Flex 50 Firmware>=4.50<5.36
Zyxel USG FLEX 50
All of the following
Zyxel USG FLEX 200 firmware>=4.50<5.36
Zyxel USG FLEX 200
All of the following
Zyxel USG FLEX 500 firmware>=4.50<5.36
Zyxel USG FLEX 500
All of the following
Zyxel USG FLEX 700 firmware>=4.50<5.36
Zyxel USG FLEX 700
All of the following
Zyxel Usg Flex 100w Firmware>=4.50<5.36
Zyxel Usg Flex 100w
All of the following
Zyxel Usg 20w-vpn Firmware>=4.16<5.36
Zyxel Usg 20w-vpn
All of the following
Zyxel Usg Flex 50w Firmware>=4.16<5.36
Zyxel Usg Flex 50w
All of the following
Zyxel Usg20-vpn Firmware>=4.30<5.36
Zyxel USG20-VPN
All of the following
Zyxel Vpn100 Firmware>=4.30<5.36
Zyxel Vpn100
All of the following
Zyxel Vpn1000 Firmware>=4.30<5.36
Zyxel Vpn1000
All of the following
Zyxel Vpn300 Firmware>=4.30<5.36
Zyxel Vpn300
All of the following
Zyxel Vpn50 Firmware>=4.30<5.36
Zyxel Vpn50

Event History

Apr 24, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2023-27990?

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

2

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.

3

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

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

4

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.

5

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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