CVE-2023-4398 - CVE House
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Status published High CVE-2023-4398

An integer overflow vulnerability in the source code of the...

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

ATP series firmware, USG FLEX series firmware, USG FLEX 50(W) series firmware, USG20(W)-VPN series firmware, VPN series firmware
Vulnerable Versions:
versions 4.32 through 5.37, versions 4.50 through 5.37, versions 4.16 through 5.37, versions 4.30 through 5.37

Timeline

Official Publish: November 28th, 2023
Last Modified: October 17th, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-190

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control
T1499 Endpoint Denial of Service
Impact