CVE-2023-34140

Medium

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.

SeverityMedium

CVSS6.5

Exploit probability—

Product

Zyxel Nxc2500 Firmware

PublishedJul 17, 2023

First seenJul 17, 2023

Weakness typeCWE-120CWE-120

How to fix

Update

zyxel usg_20w-vpn_firmware5.37 or later
zyxel usg_2200-vpn_firmware5.37 or later
zyxel usg_flex_100_firmware5.37 or later
zyxel usg_flex_100w_firmware5.37 or later
zyxel usg_flex_200_firmware5.37 or later
zyxel usg_flex_50_firmware5.37 or later
zyxel usg_flex_500_firmware5.37 or later
zyxel usg_flex_50w_firmware5.37 or later
zyxel usg_flex_700_firmware5.37 or later
zyxel zywall_atp100_firmware5.37 or later
zyxel zywall_atp100w_firmware5.37 or later
zyxel zywall_atp200_firmware5.37 or later

Vendor advisories

zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-wlan-controllers

Affected products

Product	Affected versions	Fixed in
zyxel nxc2500_firmware	6.10\(aaig.0\) ≤ v ≤ 6.10\(aaig.3\)	—
zyxel usg_20w-vpn_firmware	4.16 ≤ v < 5.37	5.37
zyxel usg_2200-vpn_firmware	4.30 ≤ v < 5.37	5.37
zyxel usg_flex_100_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_100w_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_200_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_50_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_500_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_50w_firmware	4.50 ≤ v < 5.37	5.37
zyxel usg_flex_700_firmware	4.50 ≤ v < 5.37	5.37
zyxel zywall_atp100_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_atp100w_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_atp200_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_atp500_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_atp700_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_atp800_firmware	4.32 ≤ v < 5.37	5.37
zyxel zywall_vpn100_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn2s_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn300_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn50_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn_100_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn_300_firmware	4.30 ≤ v < 5.37	5.37
zyxel zywall_vpn_50_firmware	4.30 ≤ v < 5.37	5.37
zyxel nxc5500_firmware	6.10\(aaos.0\) ≤ v ≤ 6.10\(aaos.4\)	—

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