{"cve":{"cve_id":"CVE-2023-33010","is_kev":true,"kev_date_added":"2023-06-05","kev_vendor_project":"Zyxel","kev_product":"Multiple Firewalls","kev_vulnerability_name":"Zyxel Multiple Firewalls Buffer Overflow Vulnerability","kev_short_description":"Zyxel ATP, USG FLEX, USG FLEX 50(W), USG20(W)-VPN, VPN, and ZyWALL/USG firewalls contain a buffer overflow vulnerability in the ID processing function that could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and remote code execution on an affected device.","kev_required_action":"Apply updates per vendor instructions.","kev_due_date":"2023-06-26","kev_known_ransomware":false,"kev_notes":"https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls;  https://nvd.nist.gov/vuln/detail/CVE-2023-33010","kev_cwes":["CWE-120"],"epss_score":0.28813,"epss_percentile":0.97896,"epss_as_of":"2026-06-23","description":"A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36 Patch 1, USG FLEX series firmware versions 4.50 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.25 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.25 through 5.36 Patch 1, VPN series firmware versions 4.30 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.25 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.","published_at":"2023-05-24T00:00:00Z","last_modified_at":null,"cvss_v3_score":9.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvss_v3_severity":"CRITICAL","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"total","cwes":["CWE-120"],"nvd_references":["https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-29T01:31:23.274887Z"},"effective_severity":"CRITICAL","badges":["kev"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"atp-series-firmware","product_name":"ATP series firmware","version_start":"4.32 through 5.36 Patch 1","version_start_inclusive":true,"version_end":"4.32 through 5.36 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:atp-series-firmware:4.32 through 5.36 Patch 1:4.32 through 5.36 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg20-w-vpn-firmware","product_name":"USG20(W)-VPN firmware","version_start":"4.25 through 5.36 Patch 1","version_start_inclusive":true,"version_end":"4.25 through 5.36 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg20-w-vpn-firmware:4.25 through 5.36 Patch 1:4.25 through 5.36 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-50-w-firmware","product_name":"USG FLEX 50(W) firmware","version_start":"4.25 through 5.36 Patch 1","version_start_inclusive":true,"version_end":"4.25 through 5.36 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-50-w-firmware:4.25 through 5.36 Patch 1:4.25 through 5.36 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-series-firmware","product_name":"USG FLEX series firmware","version_start":"4.50 through 5.36 Patch 1","version_start_inclusive":true,"version_end":"4.50 through 5.36 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-series-firmware:4.50 through 5.36 Patch 1:4.50 through 5.36 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"vpn-series-firmware","product_name":"VPN series firmware","version_start":"4.30 through 5.36 Patch 1","version_start_inclusive":true,"version_end":"4.30 through 5.36 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:vpn-series-firmware:4.30 through 5.36 Patch 1:4.30 through 5.36 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"zywall-usg-series-firmware","product_name":"ZyWALL/USG series firmware","version_start":"4.25 through 4.73 Patch 1","version_start_inclusive":true,"version_end":"4.25 through 4.73 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:zywall-usg-series-firmware:4.25 through 4.73 Patch 1:4.25 through 4.73 Patch 1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2023-05-24T00:00:00Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2023-06-05T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"cvss_changed","at":"2026-06-28T17:28:26.600560Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:28:26.600560Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:28:26.600560Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T01:31:23.274887Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:31:23.274887Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:31:23.274887Z","label":"SSVC decision revised","source":"vulnrichment"}]}