CVE-2023-33011: High severity Zyxel Usg 2200-vpn Firmware vulnerability

Published Jul 17, 2023
·
Updated

A format string vulnerability in the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series firmware versions 5.00 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 5.10 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 5.10 through 5.36 Patch 2, and VPN series firmware versions 5.00 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands by using a crafted PPPoE configuration on an affected device when the cloud management mode is enabled.

Affected Software

88 affected components
Zyxel Usg 2200-vpn Firmware>=5.00<5.37
Zyxel Usg 2200-vpn
Zyxel Usg Flex 100 Firmware>=5.00<5.37
Zyxel Usg Flex 100
Zyxel Usg Flex 100w Firmware>=5.00<5.37
Zyxel Usg Flex 100w
Zyxel USG FLEX 200 firmware>=5.00<5.37
Zyxel USG FLEX 200
Zyxel Usg Flex 50 Firmware>=5.00<5.37
Zyxel USG FLEX 50
Zyxel USG FLEX 500 firmware>=5.00<5.37
Zyxel USG FLEX 500
Zyxel Usg Flex 50w Firmware>=5.00<5.37
Zyxel Usg Flex 50w
Zyxel USG FLEX 700 firmware>=5.00<5.37
Zyxel USG FLEX 700
Zyxel Zywall Vpn100 Firmware>=5.00<5.37
Zyxel Zywall Vpn100
Zyxel Zywall Vpn2s Firmware>=5.00<5.37
Zyxel Zywall Vpn2s
Zyxel Zywall Vpn300 Firmware>=5.00<5.37
Zyxel Zywall Vpn300
Zyxel Zywall Vpn50 Firmware>=5.00<5.37
Zyxel Zywall Vpn50
Zyxel Zywall Vpn 100 Firmware>=5.00<5.37
Zyxel Zywall Vpn 100
Zyxel Zywall Vpn 300 Firmware>=5.00<5.37
Zyxel Zywall Vpn 300
Zyxel Zywall Vpn 50 Firmware>=5.00<5.37
Zyxel Zywall Vpn 50
Zyxel Usg 20w-vpn Firmware>=5.10<5.37
Zyxel Usg 20w-vpn
Zyxel Zywall Atp100 Firmware>=5.10<5.37
Zyxel Zywall Atp100
Zyxel Zywall Atp100w Firmware>=5.10<5.37
Zyxel Zywall Atp100w
Zyxel Zywall Atp200 Firmware>=5.10<5.37
Zyxel Zywall Atp200
Zyxel Zywall Atp500 Firmware>=5.10<5.37
Zyxel Zywall Atp500
Zyxel Zywall Atp700 Firmware>=5.10<5.37
Zyxel Zywall Atp700
Zyxel Zywall Atp800 Firmware>=5.10<5.37
Zyxel Zywall Atp800
All of the following
Zyxel Usg 2200-vpn Firmware>=5.00<5.37
Zyxel Usg 2200-vpn
All of the following
Zyxel Usg Flex 100 Firmware>=5.00<5.37
Zyxel Usg Flex 100
All of the following
Zyxel Usg Flex 100w Firmware>=5.00<5.37
Zyxel Usg Flex 100w
All of the following
Zyxel USG FLEX 200 firmware>=5.00<5.37
Zyxel USG FLEX 200
All of the following
Zyxel Usg Flex 50 Firmware>=5.00<5.37
Zyxel USG FLEX 50
All of the following
Zyxel USG FLEX 500 firmware>=5.00<5.37
Zyxel USG FLEX 500
All of the following
Zyxel Usg Flex 50w Firmware>=5.00<5.37
Zyxel Usg Flex 50w
All of the following
Zyxel USG FLEX 700 firmware>=5.00<5.37
Zyxel USG FLEX 700
All of the following
Zyxel Zywall Vpn100 Firmware>=5.00<5.37
Zyxel Zywall Vpn100
All of the following
Zyxel Zywall Vpn2s Firmware>=5.00<5.37
Zyxel Zywall Vpn2s
All of the following
Zyxel Zywall Vpn300 Firmware>=5.00<5.37
Zyxel Zywall Vpn300
All of the following
Zyxel Zywall Vpn50 Firmware>=5.00<5.37
Zyxel Zywall Vpn50
All of the following
Zyxel Zywall Vpn 100 Firmware>=5.00<5.37
Zyxel Zywall Vpn 100
All of the following
Zyxel Zywall Vpn 300 Firmware>=5.00<5.37
Zyxel Zywall Vpn 300
All of the following
Zyxel Zywall Vpn 50 Firmware>=5.00<5.37
Zyxel Zywall Vpn 50
All of the following
Zyxel Usg 20w-vpn Firmware>=5.10<5.37
Zyxel Usg 20w-vpn
All of the following
Zyxel Zywall Atp100 Firmware>=5.10<5.37
Zyxel Zywall Atp100
All of the following
Zyxel Zywall Atp100w Firmware>=5.10<5.37
Zyxel Zywall Atp100w
All of the following
Zyxel Zywall Atp200 Firmware>=5.10<5.37
Zyxel Zywall Atp200
All of the following
Zyxel Zywall Atp500 Firmware>=5.10<5.37
Zyxel Zywall Atp500
All of the following
Zyxel Zywall Atp700 Firmware>=5.10<5.37
Zyxel Zywall Atp700
All of the following
Zyxel Zywall Atp800 Firmware>=5.10<5.37
Zyxel Zywall Atp800

Event History

Jul 17, 2023
CVE Published
via MITRE·05:15 PM
Data Sourced
via MITRE·05:15 PM
DescriptionSeverityWeakness
Data Sourced
06:15 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2023-33011?

CVE-2023-33011 is a format string vulnerability in the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2.

2

Which Zyxel firmware versions are affected by CVE-2023-33011?

The Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series firmware versions 5.00 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 5.10 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 5.10 through 5.36 Patch 2, and VPN.

3

What is the severity of CVE-2023-33011?

CVE-2023-33011 has a severity rating of 8.8 (High).

4

How can I fix CVE-2023-33011?

To fix CVE-2023-33011, update your Zyxel firmware to version 5.37 or higher.

5

Where can I find more information about CVE-2023-33011?

More information about CVE-2023-33011 can be found in the Zyxel Security Advisory.

Company

Resources

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