Vulnerability · Published Nov 28, 2023 · Assigned by Zyxel

CVE-2023-4397

Medium 4.4

In plain English

A medium-severity buffer 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 0.2% (higher than 14% of all known vulnerabilities).

Severity (CVSS 3.1)4.4Medium

Exploit odds (30 days)0.2%top 85.7% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

A buffer overflow vulnerability in the Zyxel ATP series firmware version 5.37, USG FLEX series firmware version 5.37, USG FLEX 50(W) series firmware version 5.37, and USG20(W)-VPN series firmware version 5.37, could allow an authenticated local attacker with administrator privileges to cause denial-of-service (DoS) conditions by executing the CLI command with crafted strings on an affected device.

Affected products (as reported)

Vendor	Product	Versions
Zyxel	ATP series firmware	5.37
Zyxel	USG FLEX series firmware	5.37
Zyxel	USG FLEX 50(W) series firmware	5.37
Zyxel	USG20(W)-VPN series firmware	5.37

Weakness: CWE-120 · Vector: CVSS:3.1/AV:L/AC:L/PR:H/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