{"cve":{"cve_id":"CVE-2023-6399","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00649,"epss_percentile":0.46272,"epss_as_of":"2026-06-23","description":"A format string vulnerability 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, USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1, and USG FLEX H series firmware versions from 1.10 through 1.10 Patch 1 could allow an authenticated IPSec VPN user to cause DoS conditions against the “deviceid” daemon by sending a crafted hostname to an affected device if it has the “Device Insight” feature enabled.","published_at":"2024-02-20T01:42:21.027000Z","last_modified_at":null,"cvss_v3_score":5.7,"cvss_v3_vector":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"none","ssvc_automatable":false,"ssvc_technical_impact":"partial","cwes":["CWE-134"],"nvd_references":["https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps-02-20-2024"],"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":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-29T01:44:39.184534Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"A","value_label":"Adjacent"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"L","value_label":"Low"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"N","value_label":"None"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"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":"version 4.32 through 5.37 Patch 1","version_start_inclusive":true,"version_end":"version 4.32 through 5.37 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:atp-series-firmware:version 4.32 through 5.37 Patch 1:version 4.32 through 5.37 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg20-w-vpn-series-firmware","product_name":"USG20(W)-VPN series firmware","version_start":"version 4.16 through 5.37 Patch 1","version_start_inclusive":true,"version_end":"version 4.16 through 5.37 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg20-w-vpn-series-firmware:version 4.16 through 5.37 Patch 1:version 4.16 through 5.37 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-50-w-series-firmware","product_name":"USG FLEX 50(W) series firmware","version_start":"version 4.16 through 5.37 Patch 1","version_start_inclusive":true,"version_end":"version 4.16 through 5.37 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-50-w-series-firmware:version 4.16 through 5.37 Patch 1:version 4.16 through 5.37 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-h-series-firmware","product_name":"USG FLEX H series firmware","version_start":"version 1.10 through 1.10 Patch 1","version_start_inclusive":true,"version_end":"version 1.10 through 1.10 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-h-series-firmware:version 1.10 through 1.10 Patch 1:version 1.10 through 1.10 Patch 1"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-series-firmware","product_name":"USG FLEX series firmware","version_start":"version 4.50 through 5.37 Patch 1","version_start_inclusive":true,"version_end":"version 4.50 through 5.37 Patch 1","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-series-firmware:version 4.50 through 5.37 Patch 1:version 4.50 through 5.37 Patch 1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-in-firewalls-and-aps-02-20-2024","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2024-02-20T01:42:21.027000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:31:58.415164Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:31:58.415164Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:31:58.415164Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T01:44:39.184534Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:44:39.184534Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:44:39.184534Z","label":"SSVC decision revised","source":"vulnrichment"}]}