Vulnerability identifier: #VU69914

Vulnerability risk: Low

CVSSv3.1: 5.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-40603

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

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

Vendor: ZyXEL Communications Corp.

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in the CGI program. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ATP series: 4.32 - 5.31

USG FLEX series: 4.50 - 5.31

VPN series: 4.30 - 5.31

ZyWALL: 4.30 - 4.70

USG series: 4.30 - 4.70

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External links
http://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-in-firewalls

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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.