CVE-2020-13364: Critical severity zyxel nas326 vulnerability

Published Aug 6, 2020
·
Updated

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 v2V4.81(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 Software

8 affected components
Zyxel NAS326 firmware<v5.21\(aazf.9\)c0
Zyxel NAS326
Zyxel Nas520 Firmware<v5.21\(aasz.5\)c0
Zyxel NAS520
Zyxel NAS540 firmware<v5.21\(aatb.6\)c0
Zyxel NAS540
Zyxel NAS542 firmware<v5.21\(abag.6\)c0
Zyxel NAS542

Event History

Aug 6, 2020
CVE Published
via MITRE·04:54 PM
Data Sourced
via MITRE·04:54 PM
DescriptionSeverity
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Frequently Asked Questions

1

What is CVE-2020-13364?

CVE-2020-13364 is a backdoor vulnerability found in certain Zyxel products that allows remote TELNET access via a CGI script.

2

Which Zyxel products are affected by CVE-2020-13364?

CVE-2020-13364 affects the following Zyxel products: 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; and NSA310 4.22(AFK.

3

How can the CVE-2020-13364 vulnerability be exploited?

CVE-2020-13364 can be exploited by an attacker to gain remote TELNET access to the affected Zyxel products via a CGI script.

4

What is the severity of CVE-2020-13364?

CVE-2020-13364 has a severity score of 8.8, which is classified as critical.

5

Where can I find more information about CVE-2020-13364?

You can find more information about CVE-2020-13364 on the Zyxel support website: https://www.zyxel.com/support/Zyxel-security-advisory-for-NAS-remote-access-vulnerability.shtml

Contact

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