{"id":"CVE-2021-35029","aliases":["EUVD-2021-21676","GHSA-2h44-x2fr-537p"],"status":"published","title":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall...","description":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.02255,"percentile":0.83091,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-287"],"published":"2021-07-02T10:29:07Z","modified":"2026-06-17T03:56:58Z","products":[{"vendor":"zyxel","product":"atp series 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Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-35029"},{"url":"https://github.com/advisories/GHSA-2h44-x2fr-537p"}],"sources":{"cve":[{"id":"CVE-2021-35029","description":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.","status":"published","published":"2021-07-02T10:29:07Z","modified":"2024-08-04T00:33:49.831Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:33:09.864034Z"}],"euvd":[{"id":"EUVD-2021-21676","description":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.","status":"published","published":"2021-07-02T10:29:07Z","modified":"2024-08-04T00:33:49Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-03T03:24:31.533826Z"}],"ghsa":[{"id":"GHSA-2h44-x2fr-537p","title":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall...","description":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.","status":"published","published":"2022-05-24T19:06:54Z","modified":"2023-01-30T05:00:36Z","cwes":["CWE-287"],"updated_at":"2026-11-02T14:46:14.46933Z"}],"nvd":[{"id":"CVE-2021-35029","description":"An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.","status":"published","published":"2021-07-02T11:15:08.93Z","modified":"2026-06-17T03:56:58.473Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-287"],"updated_at":"2026-11-02T14:06:55.259633Z"}]}}