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Status published
Critical
CVE-2023-28771
Improper error message handling in Zyxel ZyWALL/USG series firmware versions...
Vulnerability Description
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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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Affected Vendor
Zyxel
View all reports →Affected Software
ZyWALL/USG series firmware, VPN series firmware, USG FLEX series firmware, ATP series firmware
Vulnerable Versions:
4.60 through 4.73, 4.60 through 5.35
Timeline
Official Publish:
April 25th, 2023
Last Modified:
October 21st, 2025
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H