{"cve":"CVE-2023-6764","nvd":{"published":"2024-02-20T03:15:07.870","modified":"2026-06-17T06:51:22.630","status":"Analyzed","description":"A format string vulnerability in a function of the IPSec VPN feature 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, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1},"cwes":["CWE-134"],"references":["https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps-02-20-2024","https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps-02-20-2024"],"products":["zyxel:atp100_firmware","zyxel:atp100w_firmware","zyxel:atp200_firmware","zyxel:atp500_firmware","zyxel:atp700_firmware","zyxel:atp800_firmware","zyxel:usg20-vpn_firmware","zyxel:usg20w-vpn_firmware","zyxel:usg_flex_100_firmware","zyxel:usg_flex_100ax_firmware","zyxel:usg_flex_100h_firmware","zyxel:usg_flex_100w_firmware","zyxel:usg_flex_200_firmware","zyxel:usg_flex_200h_firmware","zyxel:usg_flex_200hp_firmware","zyxel:usg_flex_500_firmware","zyxel:usg_flex_500h_firmware","zyxel:usg_flex_50_firmware","zyxel:usg_flex_50w_firmware","zyxel:usg_flex_700_firmware","zyxel:usg_flex_700h_firmware"],"source":"nvd","synced_at":"2026-10-19T21:45:59.823092188+00:00"},"epss":{"cve":"CVE-2023-6764","score":0.00889,"percentile":0.59357,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}