Live › vulnerability › CVE-2023-33009
Go to dashboardZyxel ATP, USG FLEX, USG20(W)-VPN, VPN and ZyWALL/USG firewalls have a buffer overflow in their notification function. An unauthenticated attacker can crash the device or run code on it remotely.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| Zyxel Multiple Firewalls | vendor | – | – |
| zyxel atp100 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp100 firmware | vendor | = 5.36 | – |
| zyxel atp200 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp200 firmware | vendor | = 5.36 | – |
| zyxel atp500 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp500 firmware | vendor | = 5.36 | – |
| zyxel atp100w firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp100w firmware | vendor | = 5.36 | – |
| zyxel atp700 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp700 firmware | vendor | = 5.36 | – |
| zyxel atp800 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel atp800 firmware | vendor | = 5.36 | – |
| zyxel usg flex 100 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 100 firmware | vendor | = 5.36 | – |
| zyxel usg flex 50 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 50 firmware | vendor | = 5.36 | – |
| zyxel usg flex 200 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 200 firmware | vendor | = 5.36 | – |
| zyxel usg flex 500 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 500 firmware | vendor | = 5.36 | – |
| zyxel usg flex 700 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 700 firmware | vendor | = 5.36 | – |
| zyxel usg flex 100w firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 100w firmware | vendor | = 5.36 | – |
| zyxel usg flex 50w firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg flex 50w firmware | vendor | = 5.36 | – |
| zyxel usg 20w-vpn firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg 20w-vpn firmware | vendor | = 5.36 | – |
| zyxel vpn100 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel vpn100 firmware | vendor | = 5.36 | – |
| zyxel vpn50 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel vpn50 firmware | vendor | = 5.36 | – |
| zyxel vpn300 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel vpn300 firmware | vendor | = 5.36 | – |
| zyxel vpn1000 firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel vpn1000 firmware | vendor | = 5.36 | – |
| zyxel usg20-vpn firmware | vendor | >= 4.60, < 5.36 | 5.36 |
| zyxel usg20-vpn firmware | vendor | = 5.36 | – |
| zyxel usg 40 firmware | vendor | >= 4.60, < 4.73 | 4.73 |
| zyxel usg 40 firmware | vendor | = 4.73 | – |
Unknown from the sources.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
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.
This page as .md · .json · in your agent: get_signal("CVE-2023-33009")
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