{"cve_id":"CVE-2023-28771","published":"2023-04-25T02:15:08.743000+00:00","last_modified":"2026-06-17T05:48:44.217000+00:00","vuln_status":"Analyzed","description":"Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.","cvss_version":"3.1","cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","base_score":9.8,"base_severity":"CRITICAL","attack_vector":"NETWORK","privileges_req":"NONE","user_interaction":"NONE","scope":"UNCHANGED","impact_c":"HIGH","impact_i":"HIGH","impact_a":"HIGH","cwe_ids":["CWE-78"],"in_kev":true,"kev_date_added":"2023-05-31","kev_ransomware":false,"epss_score":0.99284,"epss_percentile":0.99937,"cap_rule_version":"0.1.1","stage":"INITIAL_ACCESS","req_access":"NONE","req_vector":"NETWORK","req_user_interaction":false,"grant_access":"USER","caps":["CODE_EXEC"],"terminal":false,"cap_confidence":"high","ingested_at":"2026-09-18T10:24:26.127813+00:00","first_seen":"2023-04-25T02:15:08.743000+00:00","kev_first_seen":"2023-05-31T00:00:00+00:00","novelty_score":0.0,"novelty_reasons":[],"novelty_at":null,"vendors":["zyxel"],"products":["atp100","atp100_firmware","atp100w","atp100w_firmware","atp200","atp200_firmware","atp500","atp500_firmware","atp700","atp700_firmware","atp800","atp800_firmware","usg_flex_100","usg_flex_100_firmware","usg_flex_100w","usg_flex_100w_firmware","usg_flex_200","usg_flex_200_firmware","usg_flex_50","usg_flex_500","usg_flex_500_firmware","usg_flex_50_firmware","usg_flex_50w","usg_flex_50w_firmware","usg_flex_700","usg_flex_700_firmware","vpn100","vpn1000","vpn1000_firmware","vpn100_firmware","vpn300","vpn300_firmware","vpn50","vpn50_firmware","zywall_usg_100","zywall_usg_100_firmware","zywall_usg_310","zywall_usg_310_firmware"],"affected":[{"vendor":"zyxel","product":"atp100_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"atp100w_firmware","ranges":["≥ 4.60 and < 5.35"]},{"vendor":"zyxel","product":"atp200_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"atp500_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"atp700_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"atp800_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_100_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_100w_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_200_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_500_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_50_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_50w_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"usg_flex_700_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"vpn1000_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"vpn100_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"vpn300_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"vpn50_firmware","ranges":["≥ 4.60 and < 5.36"]},{"vendor":"zyxel","product":"zywall_usg_100_firmware","ranges":["≥ 4.60 and < 4.73","4.73"]},{"vendor":"zyxel","product":"zywall_usg_310_firmware","ranges":["4.73","≥ 4.60 and < 4.73"]}]}