CVE-2023-34140
Zyxel · published 2023-07-17
Source record Collected from the National Vulnerability Database (NVD)
Description
Description by Zyxel Corporation via the CVE Program.
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.
Status at the source
- NVD status: Modified
Affected products, as the source lists them
| Vendor | Product | Versions |
|---|---|---|
| Zyxel | ATP series firmware | 4.32 through 5.36 Patch 2: affected |
| Zyxel | USG FLEX series firmware | 4.50 through 5.36 Patch 2: affected |
| Zyxel | USG FLEX 50(W) series firmware | 4.16 through 5.36 Patch 2: affected |
| Zyxel | USG20(W)-VPN series firmware | 4.16 through 5.36 Patch 2: affected |
| Zyxel | VPN series firmware | 4.30 through 5.36 Patch 2: affected |
| Zyxel | NXC2500 firmware | 6.10(AAIG.0) through 6.10(AAIG.3): affected |
| Zyxel | NXC5500 firmware | 6.10(AAOS.0) through 6.10(AAOS.4): affected |
Products named in NVD's CPE match criteria (24)
cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_2200-vpn_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp100w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp200_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp500_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp700_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_atp800_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn2s_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn300_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn50_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn_100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn_300_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:zywall_vpn_50_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:nxc2500_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:nxc5500_firmware:*:*:*:*:*:*:*:*
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 3.1: 6.5 MEDIUM — as published by Zyxel Corporation (Secondary)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - SSVC — CISA's assessment (SSVC 2.0.3, CISA Coordinator): Exploitation: none · Automatable: no · Technical impact: partial
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-wlan-controllers
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-wlan-controllers
Source dates: published 2023-07-17, last changed 2026-06-17. DeSpy's copy of this version is dated 2026-09-28.
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