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

Exploitation Status

ACTIVE

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

N/A

CVSS v3.1 Base Metrics

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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