CVE-2023-35136: Input Validation

Published Nov 28, 2023
·
Updated

An improper input validation vulnerability in the “Quagga” package of the Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, USG20(W)-VPN series firmware versions 4.16 through 5.37, and VPN series firmware versions 4.30 through 5.37, could allow an authenticated local attacker to access configuration files on an affected device.

Affected Software

23 affected components
All of the following
Zyxel ZLD>=4.32<=5.37
Any of the following
Zyxel Atp100
Zyxel Atp100w
Zyxel ATP200
Zyxel ATP500
Zyxel Atp700
Zyxel ATP800
All of the following
Zyxel ZLD>=4.50<=5.37
Any of the following
Zyxel Usg Flex 100
Zyxel Usg Flex 100w
Zyxel USG FLEX 200
Zyxel USG FLEX 50
Zyxel USG FLEX 500
Zyxel Usg Flex 50w
Zyxel USG FLEX 700
All of the following
Zyxel ZLD>=4.16<=5.37
Any of the following
Zyxel Usg 20w-vpn
Zyxel Vpn50w
All of the following
Zyxel ZLD>=4.30<=5.37
Any of the following
Zyxel Vpn100
Zyxel Vpn1000
Zyxel Vpn300
Zyxel Vpn50

Event History

Nov 28, 2023
CVE Published
01:16 AM
Data Sourced
01:16 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-35136?

CVE-2023-35136 is an improper input validation vulnerability in the “Quagga” package of the Zyxel ATP series firmware.

2

Which Zyxel products are affected by CVE-2023-35136?

The Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, and USG20(W)-VPN series firmware versions 4.16 through 5.37 are affected by CVE-2023-35136.

3

What is the severity of CVE-2023-35136?

CVE-2023-35136 has a severity rating of medium with a CVSS score of 5.5.

4

How can I fix CVE-2023-35136?

To fix CVE-2023-35136, update the firmware of the affected Zyxel products to versions 5.37 (for ATP series), 5.37 (for USG FLEX series), 5.37 (for USG FLEX 50(W) series), or 5.37 (for USG20(W)-VPN series).

5

Where can I find more information about CVE-2023-35136?

You can find more information about CVE-2023-35136 in the Zyxel Security Advisory for Multiple Vulnerabilities in Firewalls and APs.

Contact

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