{"id":"CVE-2023-34140","aliases":["EUVD-2023-38242","GHSA-65px-649g-rj37"],"status":"published","title":"A buffer overflow vulnerability in the Zyxel ATP series firmware versions 4.32 through 5.36 Patch...","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.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.003,"percentile":0.22934,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-120"],"published":"2023-07-17T17:49:38Z","modified":"2026-06-17T06:02:58Z","products":[{"vendor":"zyxel","product":"atp series firmware"},{"vendor":"zyxel","product":"nxc2500 firmware"},{"vendor":"zyxel","product":"nxc2500_firmware"},{"vendor":"zyxel","product":"nxc5500 firmware"},{"vendor":"zyxel","product":"nxc5500_firmware"},{"vendor":"zyxel","product":"usg flex 50(w) series firmware"},{"vendor":"zyxel","product":"usg flex series firmware"},{"vendor":"zyxel","product":"usg20(w)-vpn series firmware"},{"vendor":"zyxel","product":"usg_20w-vpn_firmware"},{"vendor":"zyxel","product":"usg_2200-vpn_firmware"},{"vendor":"zyxel","product":"usg_flex_100_firmware"},{"vendor":"zyxel","product":"usg_flex_100w_firmware"},{"vendor":"zyxel","product":"usg_flex_200_firmware"},{"vendor":"zyxel","product":"usg_flex_500_firmware"},{"vendor":"zyxel","product":"usg_flex_50_firmware"},{"vendor":"zyxel","product":"usg_flex_50w_firmware"},{"vendor":"zyxel","product":"usg_flex_700_firmware"},{"vendor":"zyxel","product":"vpn series firmware"},{"vendor":"zyxel","product":"zywall_atp100_firmware"},{"vendor":"zyxel","product":"zywall_atp100w_firmware"},{"vendor":"zyxel","product":"zywall_atp200_firmware"},{"vendor":"zyxel","product":"zywall_atp500_firmware"},{"vendor":"zyxel","product":"zywall_atp700_firmware"},{"vendor":"zyxel","product":"zywall_atp800_firmware"},{"vendor":"zyxel","product":"zywall_vpn100_firmware"},{"vendor":"zyxel","product":"zywall_vpn2s_firmware"},{"vendor":"zyxel","product":"zywall_vpn300_firmware"},{"vendor":"zyxel","product":"zywall_vpn50_firmware"},{"vendor":"zyxel","product":"zywall_vpn_100_firmware"},{"vendor":"zyxel","product":"zywall_vpn_300_firmware"},{"vendor":"zyxel","product":"zywall_vpn_50_firmware"}],"references":[{"url":"https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-wlan-controllers","tags":["vendor-advisory","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-34140"},{"url":"https://github.com/advisories/GHSA-65px-649g-rj37"}],"sources":{"cve":[{"id":"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.","status":"published","published":"2023-07-17T17:49:38.175Z","modified":"2024-10-21T19:42:15.688Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:35:35.912488Z"}],"euvd":[{"id":"EUVD-2023-38242","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.","status":"published","published":"2023-07-17T17:49:38Z","modified":"2024-10-21T19:42:15Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-03T00:05:23.140259Z"}],"ghsa":[{"id":"GHSA-65px-649g-rj37","title":"A buffer overflow vulnerability in the Zyxel ATP series firmware versions 4.32 through 5.36 Patch...","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.","status":"published","published":"2023-07-17T18:31:28Z","modified":"2024-04-04T06:11:22Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:56:39.852376Z"}],"nvd":[{"id":"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.","status":"published","published":"2023-07-17T18:15:09.667Z","modified":"2026-06-17T06:02:58.96Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-120"],"updated_at":"2026-11-02T14:08:17.044696Z"}]}}