CVE-2023-33009 : A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Pat

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.

Published 2023-05-24 13:15:10

Updated 2024-04-01 15:51:49

Source Zyxel Corporation

View at NVD, CVE.org

Vulnerability category: OverflowExecute codeDenial of service

CVE-2023-33009 is in the CISA Known Exploited Vulnerabilities Catalog

CISA vulnerability name:

Zyxel Multiple Firewalls Buffer Overflow Vulnerability

CISA required action:

Apply updates per vendor instructions.

CISA description:

Zyxel ATP, USG FLEX, USG FLEX 50(W), USG20(W)-VPN, VPN, and ZyWALL/USG firewalls contain a buffer overflow vulnerability in the notification function that could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and remote code execution on an affected device.

Notes:

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls

Added on 2023-06-05 Action due date 2023-06-26

Exploit prediction scoring system (EPSS) score for CVE-2023-33009

Probability of exploitation activity in the next 30 days: 2.41%

Percentile, the proportion of vulnerabilities that are scored at or less: ~ 90 % EPSS Score History EPSS FAQ

CVSS scores for CVE-2023-33009

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source
9.8	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	3.9	5.9	NIST
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Unchanged Confidentiality: High Integrity: High Availability: High
9.8	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	3.9	5.9	Zyxel Corporation
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Unchanged Confidentiality: High Integrity: High Availability: High

CWE ids for CVE-2023-33009

CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.
Assigned by:
- nvd@nist.gov (Primary)
- security@zyxel.com.tw (Secondary)

References for CVE-2023-33009

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls

Zyxel security advisory for multiple buffer overflow vulnerabilities of firewalls | Zyxel Networks
Vendor Advisory

CVEs referencing this url

Products affected by CVE-2023-33009