CVE-2023-28771
CVSS Score
9.8
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-78 |
| Vendor | zyxel |
| Product | zywall/usg series firmware |
| Published | Apr 25, 2023 |
| Last Updated | Oct 21, 2025 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
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
References
zyxel.com: https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-remote-command-injection-vulnerability-of-firewalls packetstormsecurity.com: http://packetstormsecurity.com/files/172820/Zyxel-IKE-Packet-Decoder-Unauthenticated-Remote-Code-Execution.html cisa.gov: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-28771