Vulnerability · Published Nov 28, 2023 · Assigned by Zyxel

CVE-2023-4398

High 7.5

In plain English

A high-severity integer overflow in ATP series firmware from Zyxel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 59% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.9%top 40.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

An integer overflow vulnerability in the source code of the QuickSec IPSec toolkit used in the VPN feature of the Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, USG20(W)-VPN series firmware versions 4.16 through 5.37, and VPN series firmware versions 4.30 through 5.37, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions on an affected device by sending a crafted IKE packet.

Affected products (as reported)

Vendor	Product	Versions
Zyxel	ATP series firmware	versions 4.32 through 5.37
Zyxel	USG FLEX series firmware	versions 4.50 through 5.37
Zyxel	USG FLEX 50(W) series firmware	versions 4.16 through 5.37
Zyxel	USG20(W)-VPN series firmware	versions 4.16 through 5.37
Zyxel	VPN series firmware	versions 4.30 through 5.37

Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps vendor-advisory