CVE-2023-6399

Description

A format string vulnerability 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, USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1, and USG FLEX H series firmware versions from 1.10 through 1.10 Patch 1 could allow an authenticated IPSec VPN user to cause DoS conditions against the “deviceid” daemon by sending a crafted hostname to an affected device if it has the “Device Insight” feature enabled.

Category

5.7
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.31%
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
Affected: Zyxel USG FLEX H 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-2023-6399?
CVE-2023-6399 has been scored as a medium severity vulnerability.
How to fix CVE-2023-6399?
To fix CVE-2023-6399, 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-2023-6399 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6399 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-6399?
CVE-2023-6399 affects Zyxel ATP series firmware, Zyxel USG FLEX series firmware, Zyxel USG FLEX 50(W) series firmware, Zyxel USG20(W)-VPN series firmware, Zyxel USG FLEX H series firmware.
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