CVE-2023-35139: A cross-site scripting (XSS) vulnerability in the CGI program of the Zyxel ATP series firmware versions 5.10 through 5.37, USG FLEX series firmware versions…

PriorityP430medium6.1CVSS 3.1

AVNACLPRNUIRSCCLILAN

EPSS

0.46%

37.2th percentile

A cross-site scripting (XSS) vulnerability in the CGI program of the Zyxel ATP series firmware versions 5.10 through 5.37, USG FLEX series firmware versions 5.00 through 5.37, USG FLEX 50(W) series firmware versions 5.10 through 5.37, USG20(W)-VPN series firmware versions 5.10 through 5.37, and VPN series firmware versions 5.00 through 5.37, could allow an unauthenticated LAN-based attacker to store malicious scripts in a vulnerable device. A successful XSS attack could then result in the stored malicious scripts being executed to steal cookies when the user visits the specific CGI used for dumping ZTP logs.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
zyxel	atp_series_firmware	—	—
zyxel	usg20_vpn_series_firmware	—	—
zyxel	usg_flex_50_series_firmware	—	—
zyxel	usg_flex_series_firmware	—	—
zyxel	vpn_series_firmware	—	—
zyxel	zld	5.00 – 5.37	—
zyxel	zld	5.10 – 5.37	—

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