CVE-2020-13364

published 2020-08-06

CVE-2020-13364: A backdoor in certain Zyxel products allows remote TELNET access via a CGI script. This affects NAS520 V5.21(AASZ.4)C0, V5.21(AASZ.0)C0, V5.11(AASZ.3)C0, and…

Priority P3 48 high 8.8 CVSS 3.1

AV N AC L PR L UI N S U C H I H A H

A backdoor in certain Zyxel products allows remote TELNET access via a CGI script. 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.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
zyxel	nas326_firmware	< v5.21\(aazf.9\)c0	v5.21\(aazf.9\)c0
zyxel	nas520_firmware	< v5.21\(aasz.5\)c0	v5.21\(aasz.5\)c0
zyxel	nas540_firmware	< v5.21\(aatb.6\)c0	v5.21\(aatb.6\)c0
zyxel	nas542_firmware	< v5.21\(abag.6\)c0	v5.21\(abag.6\)c0

CVSS provenance

nvd v3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd v3.0 6.5 MEDIUM CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

nvd v2.0 9.0 CRITICAL AV:N/AC:L/Au:S/C:C/I:C/A:C

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CWE-269