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 ATP100 Firmware>=4.32<5.37
Zyxel ATP100 Firmware=5.37
Zyxel 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 ATP200 firmware
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 ATP700 Firmware>=4.32<5.37
Zyxel ATP700 Firmware=5.37
Zyxel ATP700 Firmware=5.37-patch1
Zyxel ATP700 Firmware
All of
Any of
Zyxel ATP800>=4.32<5.37
Zyxel ATP800=5.37
Zyxel ATP800=5.37-patch1
Zyxel 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
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 100h
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 200>=4.50<5.37
Zyxel USG FLEX 200=5.37
Zyxel USG FLEX 200=5.37-patch1
Zyxel USG FLEX 200 firmware
All of
Any of
Zyxel USG FLEX 200h firmware>=4.50<5.37
Zyxel USG FLEX 200h firmware=5.37
Zyxel USG FLEX 200h 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
All of
Any of
Zyxel USG FLEX 500>=4.50<5.37
Zyxel USG FLEX 500=5.37
Zyxel USG FLEX 500=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 700 firmware>=4.50<5.37
Zyxel USG FLEX 700 firmware=5.37
Zyxel USG FLEX 700 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 50
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 USG20-VPN Firmware>=4.16<5.37
Zyxel USG20-VPN Firmware=5.37
Zyxel USG20-VPN Firmware=5.37-patch1
Zyxel USG20
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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