medium
6.5
CWE
476
Advisory Published
Updated

CVE-2023-6397: Null Pointer Dereference

First published: Tue Feb 20 2024(Updated: )

A null pointer dereference vulnerability in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1 and USG FLEX series firmware versions from 4.50 through 5.37 Patch 1 could allow a LAN-based attacker to cause denial-of-service (DoS) conditions by downloading a crafted RAR compressed file onto a LAN-side host if the firewall has the “Anti-Malware” feature enabled.

Credit: security@zyxel.com.tw

Affected SoftwareAffected VersionHow to fix
Zyxel ATP series firmware>=4.32<=5.37 Patch 1
>=4.50<=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
All of
Any of
Zyxel Atp100w Firmware>=4.32<5.37
Zyxel Atp100w Firmware=5.37
Zyxel Atp100w Firmware=5.37-patch1
Zyxel Atp100w
All of
Any of
Zyxel Atp200 Firmware>=4.32<5.37
Zyxel Atp200 Firmware=5.37
Zyxel Atp200 Firmware=5.37-patch1
Zyxel 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
All of
Any of
Zyxel Atp700 Firmware>=4.32<5.37
Zyxel Atp700 Firmware=5.37
Zyxel Atp700 Firmware=5.37-patch1
Zyxel Atp700
All of
Any of
Zyxel Atp800 Firmware>=4.32<5.37
Zyxel Atp800 Firmware=5.37
Zyxel Atp800 Firmware=5.37-patch1
Zyxel Atp800
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
All of
Any of
Zyxel USG FLEX 100H Firmware>=4.50<5.37
Zyxel USG FLEX 100H Firmware=5.37
Zyxel USG FLEX 100H Firmware=5.37-patch1
Zyxel USG FLEX 100H Firmware
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
All of
Any of
Zyxel Usg Flex 200 Firmware>=4.50<5.37
Zyxel Usg Flex 200 Firmware=5.37
Zyxel Usg Flex 200 Firmware=5.37-patch1
Zyxel Usg Flex 200
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
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 50 Firmware>=4.50<5.37
Zyxel Usg Flex 50 Firmware=5.37
Zyxel Usg Flex 50 Firmware=5.37-patch1
Zyxel Usg Flex 50
All of
Any of
Zyxel Usg Flex 500 Firmware>=4.50<5.37
Zyxel Usg Flex 500 Firmware=5.37
Zyxel Usg Flex 500 Firmware=5.37-patch1
Zyxel Usg Flex 500
All of
Any of
Zyxel Usg Flex 500h Firmware>=4.50<5.37
Zyxel Usg Flex 500h Firmware=5.37
Zyxel Usg Flex 500h Firmware=5.37-patch1
Zyxel Usg Flex 500h
All of
Any of
Zyxel Usg Flex 50w Firmware>=4.50<5.37
Zyxel Usg Flex 50w Firmware=5.37
Zyxel Usg Flex 50w Firmware=5.37-patch1
Zyxel Usg Flex 50w
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
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

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