CVE-2023-22916

HIGH

Zyxel USG FLEX/ATP/VPN Series Firmware 5.00-5.35 - DoS via Configuration Parser Input Sanitization Bypass

Title source: llm

Description

The configuration parser of Zyxel ATP series firmware versions 5.10 through 5.35, USG FLEX series firmware versions 5.00 through 5.35, USG FLEX 50(W) firmware versions 5.10 through 5.35, USG20(W)-VPN firmware versions 5.10 through 5.35, and VPN series firmware versions 5.00 through 5.35, which fails to properly sanitize user input. A remote unauthenticated attacker could leverage the vulnerability to modify device configuration data, resulting in DoS conditions on an affected device if the attacker could trick an authorized administrator to switch the management mode to the cloud mode.

References (1)

Core 1

Core References

Vendor Advisory

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-of-firewalls-and-aps

Scores

CVSS v3 8.1

EPSS 0.0070

EPSS Percentile 72.2%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact total

Details

CWE

CWE-20

Status published

Products (18)

zyxel/atp100_firmware 5.10 - 5.35

zyxel/atp100w_firmware 5.10 - 5.35

zyxel/atp200_firmware 5.10 - 5.35

zyxel/atp500_firmware 5.10 - 5.35

zyxel/atp700_firmware 5.10 - 5.35

zyxel/atp800_firmware 5.10 - 5.35

zyxel/usg_20w-vpn_firmware 5.10 - 5.35

zyxel/usg_flex_100_firmware 5.00 - 5.35

zyxel/usg_flex_100w_firmware 5.00 - 5.35

zyxel/usg_flex_200_firmware 5.00 - 5.35

... and 8 more

Published Apr 24, 2023

Tracked Since Feb 18, 2026