CVE-2023-34140

Description

A buffer overflow vulnerability in the Zyxel ATP series firmware versions 4.32 through 5.36 Patch 2, USG FLEX series firmware versions 4.50 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 4.16 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 4.16 through 5.36 Patch 2, VPN series firmware versions 4.30 through 5.36 Patch 2, NXC2500 firmware versions 6.10(AAIG.0) through 6.10(AAIG.3), and NXC5500 firmware versions 6.10(AAOS.0) through 6.10(AAOS.4), could allow an unauthenticated, LAN-based attacker to cause denial of service (DoS) conditions by sending a crafted request to the CAPWAP daemon.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.10%
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 VPN series firmware
Affected: Zyxel NXC2500 firmware
Affected: Zyxel NXC5500 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-wlan-controllers vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-34140?
CVE-2023-34140 has been scored as a medium severity vulnerability.
How to fix CVE-2023-34140?
To fix CVE-2023-34140, 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-2023-34140 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-34140 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-2023-34140?
CVE-2023-34140 affects Zyxel ATP series firmware, Zyxel USG FLEX series firmware, Zyxel USG FLEX 50(W) series firmware, Zyxel USG20(W)-VPN series firmware, Zyxel VPN series firmware, Zyxel NXC2500 firmware, Zyxel NXC5500 firmware.
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