CVE-2020-29583: Zyxel Multiple Products Use of Hard-Coded Credentials Vulnerability

Published Dec 22, 2020
·
Updated

Firmware version 4.60 of Zyxel USG devices contains an undocumented account (zyfwp) with an unchangeable password. The password for this account can be found in cleartext in the firmware. This account can be used by someone to login to the ssh server or web interface with admin privileges.

Other sources

Zyxel firewalls (ATP, USG, VM) and AP Controllers (NXC2500 and NXC5500) contain a use of hard-coded credentials vulnerability in an undocumented account ("zyfwp") with an unchangeable password.

CISA

Affected Software

91 affected components
Zyxel Multiple Products
Zyxel Usg20-vpn Firmware=4.60
Zyxel USG20-VPN
Zyxel Usg20w-vpn Firmware=4.60
Zyxel USG20W-VPN
Zyxel Usg40 Firmware=4.60
Zyxel USG40
Zyxel Usg40w Firmware=4.60
Zyxel USG40W
Zyxel Usg60 Firmware=4.60
Zyxel USG60
Zyxel Usg60w Firmware=4.60
Zyxel USG60W
Zyxel Usg110 Firmware=4.60
Zyxel USG110
Zyxel Usg210 Firmware=4.60
Zyxel USG210
Zyxel Usg310 Firmware=4.60
Zyxel USG310
Zyxel Usg1100 Firmware=4.60
Zyxel USG1100
Zyxel Usg1900 Firmware=4.60
Zyxel USG1900
Zyxel Usg2200 Firmware=4.60
Zyxel Usg2200
Zyxel Zywall110 Firmware=4.60
Zyxel Zywall110
Zyxel Zywall310 Firmware=4.60
Zyxel Zywall310
Zyxel Zywall1100 Firmware=4.60
Zyxel Zywall1100
All of the following
Zyxel Usg20-vpn Firmware=4.60
Zyxel USG20-VPN
All of the following
Zyxel Usg20w-vpn Firmware=4.60
Zyxel USG20W-VPN
All of the following
Zyxel Usg40 Firmware=4.60
Zyxel USG40
All of the following
Zyxel Usg40w Firmware=4.60
Zyxel USG40W
All of the following
Zyxel Usg60 Firmware=4.60
Zyxel USG60
All of the following
Zyxel Usg60w Firmware=4.60
Zyxel USG60W
All of the following
Zyxel Usg110 Firmware=4.60
Zyxel USG110
All of the following
Zyxel Usg210 Firmware=4.60
Zyxel USG210
All of the following
Zyxel Usg310 Firmware=4.60
Zyxel USG310
All of the following
Zyxel Usg1100 Firmware=4.60
Zyxel USG1100
All of the following
Zyxel Usg1900 Firmware=4.60
Zyxel USG1900
All of the following
Zyxel Usg2200 Firmware=4.60
Zyxel Usg2200
All of the following
Zyxel Zywall110 Firmware=4.60
Zyxel Zywall110
All of the following
Zyxel Zywall310 Firmware=4.60
Zyxel Zywall310
All of the following
Zyxel Zywall1100 Firmware=4.60
Zyxel Zywall1100
All of the following
Zyxel Atp100 Firmware=4.60
Zyxel Atp100
All of the following
Zyxel Atp100w Firmware=4.60
Zyxel Atp100w
All of the following
Zyxel Atp200 Firmware=4.60
Zyxel ATP200
All of the following
Zyxel Atp500 Firmware=4.60
Zyxel ATP500
All of the following
Zyxel Atp700 Firmware=4.60
Zyxel Atp700
All of the following
Zyxel Atp800 Firmware=4.60
Zyxel ATP800
All of the following
Zyxel Vpn50 Firmware=4.60
Zyxel Vpn50
All of the following
Zyxel Vpn100 Firmware=4.60
Zyxel Vpn100
All of the following
Zyxel Vpn300 Firmware=4.60
Zyxel Vpn300
All of the following
Zyxel Vpn1000 Firmware=4.60
Zyxel Vpn1000
All of the following
Zyxel Usg Flex 100 Firmware=4.60
Zyxel Usg Flex 100
All of the following
Zyxel Usg Flex 100w Firmware=4.60
Zyxel Usg Flex 100w
All of the following
Zyxel USG FLEX 200 firmware=4.60
Zyxel USG FLEX 200
All of the following
Zyxel USG FLEX 500 firmware=4.60
Zyxel USG FLEX 500
All of the following
Zyxel USG FLEX 700 firmware=4.60
Zyxel USG FLEX 700

Event History

Dec 22, 2020
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM
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Frequently Asked Questions

1

What is CVE-2020-29583?

CVE-2020-29583 is a vulnerability found in Zyxel multiple products that allows unauthorized access with admin privileges.

2

How severe is CVE-2020-29583?

CVE-2020-29583 has a severity rating of 9.8 out of 10, making it a critical vulnerability.

3

Which Zyxel devices are affected by CVE-2020-29583?

Zyxel devices with firmware version 4.60, including USG20, USG20W, USG40, USG40W, USG60, USG60W, USG110, USG210, USG310, USG1100, USG1900, USG2200, Zywall110, Zywall310, and Zywall1100, are affected by CVE-2020-29583.

4

How can I fix CVE-2020-29583?

To fix CVE-2020-29583, you need to upgrade the firmware of the affected Zyxel device to version 4.60 Patch 1 or later.

5

Where can I find more information about CVE-2020-29583?

You can find more information about CVE-2020-29583 on the Zyxel support forum and the official Zyxel website.

Contact

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