{"schemaVersion":3,"id":"CVE-2020-13365","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Certain Zyxel products have a locally accessible binary that allows a non-root user to generate a password for an undocumented user account that can be used for a TELNET session as root. This affects NAS520 V5.21(AASZ.4)C0, V5.21(AASZ.0)C0, V5.11(AASZ.3)C0, and V5.11(AASZ.0)C0; NAS542 V5.11(ABAG.0)C0, V5.20(ABAG.1)C0, and V5.21(ABAG.3)C0; NSA325 v2_V4.81(AALS.0)C0 and V4.81(AAAJ.1)C0; NSA310 4.22(AFK.0)C0 and 4.22(AFK.1)C0; NAS326 V5.21(AAZF.8)C0, V5.11(AAZF.4)C0, V5.11(AAZF.2)C0, and V5.11(AAZF.3)C0; NSA310S V4.75(AALH.2)C0; NSA320S V4.75(AANV.2)C0 and V4.75(AANV.1)C0; NSA221 V4.41(AFM.1)C0; and NAS540 V5.21(AATB.5)C0 and V5.21(AATB.3)C0.","dates":{"published":"2020-08-06T16:56:21.000Z","modified":"2024-08-04T12:18:17.736Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9,"severity":"high","version":"2.0","versionLabel":"v2.0","source":"NVD","vector":"AV:N/AC:L/Au:S/C:C/I:C/A:C","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.0","versionLabel":"v3.0","source":"CVE.org","score":8.4,"severity":"high","vector":"CVSS:3.0/AC:L/AV:L/A:H/C:H/I:H/PR:N/S:U/UI:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":8.8,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.0","versionLabel":"v3.0","source":"NVD","score":8.4,"severity":"high","vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":9,"severity":"high","vector":"AV:N/AC:L/Au:S/C:C/I:C/A:C","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00972,"percentile":0.61385,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.00972},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00972,"percentile":0.61385}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00972,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score"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