Is CVE-2023-28771 actively exploited?

CVE-2023-28771 has no public evidence of in-the-wild exploitation as of 2025-10-27.

What is the CVSS score for CVE-2023-28771?

CVE-2023-28771 has a CVSS score of 9.8 (CRITICAL severity). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

How do I patch CVE-2023-28771?

Patch guidance is available from zyxel security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2023-28771.

Fix CVE-2023-28771 - CRITICAL zyxel atp100 firmware

Q: Which products are affected by CVE-2023-28771?

21 products: zyxel atp100 firmware, zyxel atp100w firmware, zyxel atp200 firmware, zyxel atp500 firmware, zyxel atp700 firmware, and 16 more.

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.

CVSS Metrics

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
Weaknesses: CWE-78 · OS Command Injection CWE-78 · OS Command Injection

Metadata

Primary Vendor: ZYXEL
Published: 4/25/2023
Last Modified: 10/27/2025
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

zyxel : atp100_firmwarezyxel : atp100w_firmwarezyxel : atp200_firmwarezyxel : atp500_firmwarezyxel : atp700_firmwarezyxel : atp800_firmwarezyxel : usg_flex_100_firmwarezyxel : usg_flex_100w_firmwarezyxel : usg_flex_200_firmwarezyxel : usg_flex_50_firmwarezyxel : usg_flex_500_firmwarezyxel : usg_flex_50w_firmwarezyxel : usg_flex_700_firmwarezyxel : vpn100_firmwarezyxel : vpn1000_firmwarezyxel : vpn300_firmwarezyxel : vpn50_firmwarezyxel : zywall_usg_310_firmwarezyxel : zywall_usg_310_firmwarezyxel : zywall_usg_100_firmwarezyxel : zywall_usg_100_firmware

Remediation Guidance

Executive Summary

View on NIST NVD