CVE-2023-33009

CriticalCVSS 9.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

Description

A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-120

Affected software

Vendor	Product	Versions
Zyxel	ATP series firmware	4.60 through 5.36 Patch 1
Zyxel	USG FLEX series firmware	4.60 through 5.36 Patch 1
Zyxel	USG FLEX 50(W) firmware	4.60 through 5.36 Patch 1
Zyxel	USG20(W)-VPN firmware	4.60 through 5.36 Patch 1
Zyxel	VPN series firmware	4.60 through 5.36 Patch 1
Zyxel	ZyWALL/USG series firmware	4.60 through 4.73 Patch 1

References

Timeline

Published: May 24, 2023
Last modified: Jun 17, 2026
Added to CISA KEV: Jun 5, 2023
NVD status: Analyzed

Related CVEs from 2023

CVE-2023-33015.6A flaw was found in QEMU. The async nature of hot-unplug enables a race scenario where the net device backend is cleared before the virtio-n CVE-2023-330109.8A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36 Patch 1, USG FLEX seri CVE-2023-330118.8A format string vulnerability in the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series firmware versions 5.00 th CVE-2023-330128.8A command injection vulnerability in the configuration parser of the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX CVE-2023-330138.8A post-authentication command injection vulnerability in the NTP feature of Zyxel NBG6604 firmware version V1.01(ABIR.1)C0 could allow an au CVE-2023-330146.8Information disclosure in Core services while processing a Diag command.CVE-2023-330157.5Transient DOS in WLAN Firmware while interpreting MBSSID IE of a received beacon frame.CVE-2023-330167.5Transient DOS in WLAN firmware while parsing MLO (multi-link operation).CVE-2023-330177.8Memory corruption in Boot while running a ListVars test in UEFI Menu during boot.CVE-2023-330187.8Memory corruption while using the UIM diag command to get the operators name.CVE-2023-330197.5Transient DOS in WLAN Host while doing channel switch announcement (CSA), when a mobile station receives invalid channel in CSA IE.CVE-2023-33027.8Improper Neutralization of Formula Elements in a CSV File in GitHub repository admidio/admidio prior to 4.2.9.