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CVE-2023-28771

Published: Apr 25, 2023Updated: Oct 27, 2025 Sources: CVE List NVD BDUCWE-78
9.8CRITICAL
NVD MITRE
EPSS Score
99.3%
Top 0.1%
CISA KEV
Active Exploitation
Since May 31, 2023
Exploits
1 Known
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-78

Affected Products

Zyxel Communications Corp.
commercial·TWaka Zyxel
ZyWALL/USG series firmware
Networking Infrastructure
VPN series firmware
Networking Infrastructure
USG FLEX series firmware
Networking Infrastructure
ATP series firmware
Networking Infrastructure
atp100 firmware
Networking Infrastructure
atp100w firmware
Networking Infrastructure
atp200 firmware
Networking Infrastructure
atp500 firmware
Networking Infrastructure
and 34 more affected products View all →

Exploitability

CISA Known Exploited Vulnerability
Added to KEV:May 31, 2023
Remediation due:Jun 21, 2023

Required action: Apply updates per vendor instructions.

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Execution
View detailed technique mapping

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-remote-command-injection-vulnerability-of-firewalls
zyxel.com
http://packetstormsecurity.com/files/172820/Zyxel-IKE-Packet-Decoder-Unauthenticated-Remote-Code-Execution.html
packetstormsecurity.com
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-28771
cisa.gov
News mentions
2

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