CVE-2022-30525: Zyxel Multiple Firewalls OS Command Injection Vulnerability

Critical severity, CVSS 9.8. Actively exploited: in CISA KEV since 2022-05-16. EPSS: 99.9% chance of exploitation in the next 30 days.

A OS command injection vulnerability in the CGI program of Zyxel USG FLEX 100(W) firmware versions 5.00 through 5.21 Patch 1, USG FLEX 200 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 500 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 700 firmware versions 5.00 through 5.21 Patch 1, USG FLEX 50(W) firmware versions 5.10 through 5.21 Patch 1, USG20(W)-VPN firmware versions 5.10 through 5.21 Patch 1, ATP series firmware versions 5.10 through 5.21 Patch 1, VPN series firmware versions 4.60 through 5.21 Patch 1, which could allow an attacker to modify specific files and then execute some OS commands on a vulnerable device.

Affected products

Zyxel ATP100 Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel ATP100W Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel ATP200 Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel ATP500 Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel ATP700 Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel ATP800 Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel USG20W-VPN Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel Usg Flex 100w Firmware: from 5.00, before 5.30 (fixed in 5.30)
Zyxel Usg Flex 200 Firmware: from 5.00, before 5.30 (fixed in 5.30)
Zyxel Usg Flex 500 Firmware: from 5.00, up to and including 5.30
Zyxel Usg Flex 50w Firmware: from 5.10, before 5.30 (fixed in 5.30)
Zyxel Usg Flex 700 Firmware: from 5.00, before 5.30 (fixed in 5.30)
Zyxel VPN1000 Firmware: from 4.60, before 5.30 (fixed in 5.30)
Zyxel VPN100 Firmware: from 4.60, before 5.30 (fixed in 5.30)
Zyxel VPN300 Firmware: from 4.60, before 5.30 (fixed in 5.30)
Zyxel VPN50 Firmware: from 4.60, before 5.30 (fixed in 5.30)

Published 2022-05-12. Last modified 2026-06-17.