CVE-2023-28771NVD

Vulnerability Summary

Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.

Severity Level

CRITICAL(9.8)

Published Date

Apr 25, 2023

Last Modified

Oct 21, 2025

PoC

Available(Metasploit)

Exploitation Status

ACTIVE

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-78: OS Command Injection ↗

The software constructs all or part of an OS command using externally-influenced input, but does not properly neutralize special elements.

CVSS v3.1 Base Metrics — Score 9.8 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Zyxel ZyWALL/USG series firmware >= 4.60 through 4.73
Zyxel VPN series firmware >= 4.60 through 5.35
Zyxel USG FLEX series firmware >= 4.60 through 5.35
Zyxel ATP series firmware >= 4.60 through 5.35

Patched Versions

Not provided by cveorg for this CVE.

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