CVE-2023-27991 | BDVDB-2026-200872 Detail

ZyxelATP series firmware

Description#

The post-authentication command injection vulnerability in the CLI command of Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow an authenticated attacker to execute some OS commands remotely.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.

Weaknesses#

CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

References#

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls

Exploit#

No public exploit known

History#

Version 12023-04-24Record published in the CVE List.
Version 22025-02-04Most recent update recorded in the CVE List.

Published

Published: 2023-04-24
Last modified: 2025-02-04

Vendor information

Vendor: Zyxel
Product: ATP series firmware

All Zyxel vulnerabilities

Score

8.8 High

EPSS

1.4%, Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 73.6.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Command Injection

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
4.32 through 5.35
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

8.8 High

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

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	Low
User Interaction	None
Scope	Unchanged
Confidentiality	High
Integrity	High
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).