OPNsense Reflected Cross-Site Scripting Vulnerability in VPN IPsec Settings

A reflected cross-site scripting vulnerability has been identified in OPNsense version 19.1. This issue allows attackers to inject malicious scripts by exploiting the 'passthrough_networks' parameter in 'vpn_ipsec_settings.php'. By crafting POST requests with JavaScript payloads, attackers can execute arbitrary code in the browsers of users.

Impact

Exploitation of this vulnerability allows for reflected cross-site scripting, where injected scripts are executed in the context of the user's browser.

Reproduction

To reproduce this vulnerability, send a POST request to 'vpn_ipsec_settings.php' with a payload in the 'passthrough_networks' parameter. The injected script will be executed as soon as the response is received.

Remediation

Users are advised to update to OPNsense version 19.1.1, which addresses this vulnerability.