CVE-2023-6764

Description

A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
EPSS 1.73% Top 20%
Vendor Advisory zyxel.com
Affected: Zyxel ATP series firmware
Affected: Zyxel USG FLEX series firmware
Affected: Zyxel USG FLEX 50(W) series firmware
Affected: Zyxel USG20(W)-VPN series firmware
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps-02-20-2024 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-6764?
CVE-2023-6764 has been scored as a high severity vulnerability.
How to fix CVE-2023-6764?
To fix CVE-2023-6764, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-6764 being actively exploited in the wild?
It is possible that CVE-2023-6764 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-6764?
CVE-2023-6764 affects Zyxel ATP series firmware, Zyxel USG FLEX series firmware, Zyxel USG FLEX 50(W) series firmware, Zyxel USG20(W)-VPN series firmware.
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