AEGLIX vulnerability intelligence

CVE-2023-33009

CRITICAL · CVSS 9.8 · Analyzed

Published: 2023-05-24 · Updated: 2026-06-17 · Source: NVD

Vulnerability overview

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.

Severity and scoring

CVSS score: 9.8 · CRITICAL
CVSS version: 3.1
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses: CWE-120

CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.

Known exploitation and remediation

Listed in CISA’s Known Exploited Vulnerabilities catalog.

Affected product: Zyxel · Multiple Firewalls
Added to catalog: 2023-06-05
Required action: Apply updates per vendor instructions.
CISA remediation due date: 2023-06-26

CISA deadlines apply to the organizations covered by its directives. Confirm your own remediation requirements.

Verify affected versions and patch availability in the vendor advisory before making changes.

Affected products and versions

cpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp100_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp200_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp200_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp500_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp500_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp100w_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100w_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp700_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp700_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:atp800_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp800_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_100_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_50_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_50_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_200_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_200_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_500_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_500_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_700_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_700_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_100w_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100w_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_flex_50w_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_50w_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:vpn100_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn100_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:vpn50_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn50_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:vpn300_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn300_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:vpn1000_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn1000_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg20-vpn_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 5.36
cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 4.73
cpe:2.3:o:zyxel:usg_40_firmware:4.73:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40_firmware:4.73:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40w_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 4.73
cpe:2.3:o:zyxel:usg_40w_firmware:4.73:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40w_firmware:4.73:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60w_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 4.73
cpe:2.3:o:zyxel:usg_60w_firmware:4.73:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60w_firmware:4.73:patch1:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60_firmware:*:*:*:*:*:*:*:*
From (inclusive): 4.60
Before (exclusive): 4.73
cpe:2.3:o:zyxel:usg_60_firmware:4.73:-:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60_firmware:4.73:patch1:*:*:*:*:*:*

These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.

Advisories and references

Explore official sources

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