#VU61723 Improper Authentication in ZyXEL Communications Corp. products - CVE-2022-0342

Vulnerability identifier: #VU61723

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2022-0342

CWE-ID: CWE-287

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
USG series
Client/Desktop applications / Antivirus software/Personal firewalls
USG FLEX series
Client/Desktop applications / Antivirus software/Personal firewalls
VPN series
Client/Desktop applications / Antivirus software/Personal firewalls
ZyWALL
Other software / Other software solutions
NSG series
Hardware solutions / Routers for home users
ATP series
Hardware solutions / Routers for home users

Vendor: ZyXEL Communications Corp.

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to missing authentication checks in the web interface. A remote attacker can bypass authentication process and obtain administrative access to the device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

USG series: before 4.71

ZyWALL: before 4.71

USG FLEX series: before 5.21

VPN series: before 5.21

NSG series: before 1.33p4_WK11

ATP series: before 5.21

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External links
https://www.zyxel.com/support/Zyxel-security-advisory-for-authentication-bypass-vulnerability-of-firewalls.shtml

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.