TRENDnet TEW-824DRU Cross-Site Scripting Vulnerability in Web Interface

A stored cross-site scripting vulnerability has been identified in the TRENDnet TEW-824DRU router, specifically in the web interface component 'apply_sec.cgi', within the 'sub_420A78' function. This vulnerability affects firmware versions 1.010B01 and 1.04B01. The issue arises from improper handling of the 'language' parameter, which allows remote attackers to inject arbitrary web scripts or HTML. Once injected, the malicious script is executed in the context of the user, potentially leading to a denial-of-service condition on the web interface.

Impact

Exploitation of this vulnerability allows for stored cross-site scripting, where injected scripts are executed in the context of the user. This injection corrupts the device's global language setting, disrupting the HTML structure of the login and management pages. As a result, the web interface becomes unresponsive, causing a persistent denial-of-service condition.

Reproduction

To reproduce this vulnerability, send a POST request to 'apply_sec.cgi' with a crafted 'language' parameter that includes JavaScript payloads, such as an alert script. This payload will be reflected in the HTML response, executed as a script, and disrupt normal web interface functionality.