Cross-site scripting in ZyXEL Communications Corp. products - CVE-2021-35030

Vulnerability identifier: #VU55434

CSH Severity: Low

CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]

CVE-ID: CVE-2021-35030

CWE-ID: CWE-79

Exploitation vector: Remote access

Exploit availability: No public exploit available

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 authenticated 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.

GS1900-8
GS1900-8HP
GS1900-10HP
GS1900-16
GS1900-24E
GS1900-24EP
GS1900-24
GS1900-24HP
GS1900-24HPv2
GS1900-48
GS1900-48HP
GS1900-48HPv2

Install update from vendor's website.

GS1900-8 - update to 2.70
GS1900-8HP - update to 2.70
GS1900-10HP - update to 2.70
GS1900-16 - update to 2.70
GS1900-24E - update to 2.70
GS1900-24EP - update to 2.70
GS1900-24 - update to 2.70
GS1900-24HP - update to 2.70
GS1900-24HPv2 - update to 2.70
GS1900-48 - update to 2.70
GS1900-48HP - update to 2.70
GS1900-48HPv2 - update to 2.70

• https://www.zyxel.com/support/Zyxel_security_advisory_for_XSS_vulnerability_of_GS1900_series_switches.shtml

• Cross-site scripting in Zyxel GS1900 Series Switches