{"cve":{"cve_id":"CVE-2023-27990","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":0.00344,"epss_percentile":0.26117,"epss_as_of":"2026-06-23","description":"The cross-site scripting (XSS) vulnerability in Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow an authenticated attacker with administrator privileges to store malicious scripts in a vulnerable device. A successful XSS attack could then result in the stored malicious scripts being executed when the user visits the Logs page of the GUI on the device.","published_at":"2023-04-24T00:00:00Z","last_modified_at":null,"cvss_v3_score":4.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-79"],"nvd_references":["https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-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":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:19:44.217771Z"},"effective_severity":"MEDIUM","badges":[],"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":"H","value_label":"High"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"L","value_label":"Low"},{"metric":"I","name":"Integrity","value":"L","value_label":"Low"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"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 5.35","version_start_inclusive":true,"version_end":"4.32 through 5.35","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:atp-series-firmware:4.32 through 5.35:4.32 through 5.35"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg20-w-vpn-firmware","product_name":"USG20(W)-VPN firmware","version_start":"4.16 through 5.35","version_start_inclusive":true,"version_end":"4.16 through 5.35","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg20-w-vpn-firmware:4.16 through 5.35:4.16 through 5.35"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-50-w-firmware","product_name":"USG FLEX 50(W) firmware","version_start":"4.16 through 5.35","version_start_inclusive":true,"version_end":"4.16 through 5.35","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-50-w-firmware:4.16 through 5.35:4.16 through 5.35"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"usg-flex-series-firmware","product_name":"USG FLEX series firmware","version_start":"4.50 through 5.35","version_start_inclusive":true,"version_end":"4.50 through 5.35","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:usg-flex-series-firmware:4.50 through 5.35:4.50 through 5.35"},{"vendor_slug":"zyxel","vendor_name":"Zyxel","product_slug":"vpn-series-firmware","product_name":"VPN series firmware","version_start":"4.30 through 5.35","version_start_inclusive":true,"version_end":"4.30 through 5.35","version_end_inclusive":true,"cpe23_uri":"cve5:zyxel:vpn-series-firmware:4.30 through 5.35:4.30 through 5.35"}],"exploit_refs":[],"news":[],"references":[{"url":"https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2023-04-24T00:00:00Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:27:27.289124Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:27:27.289124Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:27:27.289124Z","label":"CVSS score revised","source":"cvelistv5"}]}