high
8.1
CWE
134
Advisory Published
Updated

CVE-2023-6764

First published: Tue Feb 20 2024(Updated: )

A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.

Credit: security@zyxel.com.tw

Affected SoftwareAffected VersionHow to fix
Zyxel ATP series firmware>=4.32<5.37 Patch 1
Zyxel USG FLEX series firmware>=4.50<5.37 Patch 1
Zyxel USG FLEX 50(W) series firmware>=4.16<5.37 Patch 1
Zyxel USG 20w-VPN Firmware>=4.16<5.37 Patch 1
All of
Any of
Zyxel ZyWall ATP100 Firmware>=4.32<5.37
Zyxel ZyWall ATP100 Firmware=5.37
Zyxel ZyWall ATP100 Firmware=5.37-patch1
Zyxel ATP100 Firmware
All of
Any of
Zyxel ATP100W Firmware>=4.32<5.37
Zyxel ATP100W Firmware=5.37
Zyxel ATP100W Firmware=5.37-patch1
Zyxel ATP100W Firmware
All of
Any of
Zyxel ATP200 firmware>=4.32<5.37
Zyxel ATP200 firmware=5.37
Zyxel ATP200 firmware=5.37-patch1
Zyxel Zywall ATP200
All of
Any of
Zyxel ATP500 Firmware>=4.32<5.37
Zyxel ATP500 Firmware=5.37
Zyxel ATP500 Firmware=5.37-patch1
Zyxel ATP500 Firmware
All of
Any of
Zyxel Zywall ATP700>=4.32<5.37
Zyxel Zywall ATP700=5.37
Zyxel Zywall ATP700=5.37-patch1
Zyxel ATP700 Firmware
All of
Any of
Zyxel Zywall ATP800 Firmware>=4.32<5.37
Zyxel Zywall ATP800 Firmware=5.37
Zyxel Zywall ATP800 Firmware=5.37-patch1
Zyxel Zywall ATP800 Firmware
All of
Any of
Zyxel USG Flex 100 firmware>=4.50<5.37
Zyxel USG Flex 100 firmware=5.37
Zyxel USG Flex 100 firmware=5.37-patch1
Zyxel USG Flex 100 firmware
All of
Any of
Zyxel USG FLEX 100ax firmware>=4.50<5.37
Zyxel USG FLEX 100ax firmware=5.37
Zyxel USG FLEX 100ax firmware=5.37-patch1
Zyxel USG FLEX 100ax firmware
All of
Any of
Zyxel USG FLEX 100ax firmware>=4.50<5.37
Zyxel USG FLEX 100ax firmware=5.37
Zyxel USG FLEX 100ax firmware=5.37-patch1
Zyxel USG Flex 100HP
All of
Any of
Zyxel USG FLEX 100w firmware>=4.50<5.37
Zyxel USG FLEX 100w firmware=5.37
Zyxel USG FLEX 100w firmware=5.37-patch1
Zyxel USG FLEX 100w firmware
All of
Any of
Zyxel USG FLEX firmware>=4.50<5.37
Zyxel USG FLEX firmware=5.37
Zyxel USG FLEX firmware=5.37-patch1
Zyxel USG FLEX 200 firmware
All of
Any of
Zyxel USG Flex 200HP Firmware>=4.50<5.37
Zyxel USG Flex 200HP Firmware=5.37
Zyxel USG Flex 200HP Firmware=5.37-patch1
Zyxel USG FLEX 200h firmware
All of
Any of
Zyxel USG Flex 200HP Firmware>=4.50<5.37
Zyxel USG Flex 200HP Firmware=5.37
Zyxel USG Flex 200HP Firmware=5.37-patch1
Zyxel USG Flex 200HP Firmware
All of
Any of
Zyxel USG FLEX firmware>=4.50<5.37
Zyxel USG FLEX firmware=5.37
Zyxel USG FLEX firmware=5.37-patch1
Zyxel USG FLEX 500 firmware
All of
Any of
Zyxel USG FLEX 500h>=4.50<5.37
Zyxel USG FLEX 500h=5.37
Zyxel USG FLEX 500h=5.37-patch1
Zyxel USG FLEX 500h firmware
All of
Any of
Zyxel USG FLEX firmware>=4.50<5.37
Zyxel USG FLEX firmware=5.37
Zyxel USG FLEX firmware=5.37-patch1
Zyxel USG FLEX 700 firmware
All of
Any of
Zyxel USG FLEX 700h firmware>=4.50<5.37
Zyxel USG FLEX 700h firmware=5.37
Zyxel USG FLEX 700h firmware=5.37-patch1
Zyxel USG FLEX 700h firmware
All of
Any of
Zyxel USG FLEX 50(W) series firmware>=4.16<5.37
Zyxel USG FLEX 50(W) series firmware=5.37
Zyxel USG FLEX 50(W) series firmware=5.37-patch1
Zyxel USG FLEX 50w
All of
Any of
Zyxel USG FLEX 50w>=4.16<5.37
Zyxel USG FLEX 50w=5.37
Zyxel USG FLEX 50w=5.37-patch1
Zyxel USG FLEX 50(W) series firmware
All of
Any of
Zyxel USG20W-VPN Firmware>=4.16<5.37
Zyxel USG20W-VPN Firmware=5.37
Zyxel USG20W-VPN Firmware=5.37-patch1
Zyxel USG20W-VPN Firmware
All of
Any of
Zyxel USG 20W-VPN Firmware>=4.16<5.37
Zyxel USG 20W-VPN Firmware=5.37
Zyxel USG 20W-VPN Firmware=5.37-patch1
Zyxel USG20W-VPN Firmware

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-6764?

    CVE-2023-6764 is classified as a critical vulnerability due to its potential impact on the security of affected Zyxel devices.

  • How do I fix CVE-2023-6764?

    To address CVE-2023-6764, users should upgrade to the latest patched version of the Zyxel firmware available for their devices.

  • Which Zyxel products are affected by CVE-2023-6764?

    CVE-2023-6764 affects various Zyxel devices including ATP series, USG FLEX series, USG FLEX 50(W), and USG20(W)-VPN firmware versions.

  • What type of vulnerability is CVE-2023-6764?

    CVE-2023-6764 is a format string vulnerability that could allow for code execution or crashes in the affected Zyxel devices.

  • What are the ramifications of not addressing CVE-2023-6764?

    Failing to address CVE-2023-6764 may lead to unauthorized access or control over affected Zyxel devices, significantly compromising network security.

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