CVE-2025-8078

High

Description

A post-authentication command injection vulnerability in Zyxel ATP series firmware versions from V4.32 through V5.40, USG FLEX series firmware versions from V4.50 through V5.40, USG FLEX 50(W) series firmware versions from V4.16 through V5.40, and USG20(W)-VPN series firmware versions from V4.16 through V5.40 could allow an authenticated attacker with administrator privileges to execute operating system (OS) commands on the affected device by passing a crafted string as an argument to a CLI command.

SeverityHigh

CVSS7.2

Exploit probability—

Product

Zyxel Zld

PublishedOct 21, 2025

First seenOct 21, 2025

Weakness typeCWE-78OS command injection

How to fix

Update

zyxel zld5.41 or later

Vendor advisories

zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-post-authentication-command-injection-and-missing-authorization-vulnerabilities-in-zld-firewalls-10-21-2025

Affected products

Product	Affected versions	Fixed in
zyxel zld	4.32 ≤ v < 5.41, 4.50 ≤ v < 5.41, 4.16 ≤ v < 5.41	5.41

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