Netsweeper Cross-Site Scripting Scanner

Netsweeper is a web content filtering platform commonly used by educational institutions, corporations, and service providers to manage internet access. Its software is designed to provide a secure browsing environment by blocking access to inappropriate or harmful content online. Users can implement detailed control over web traffic and enforce content policies through its administrative console. Netsweeper aims to improve network security and internet management within organizational settings. It powers policy enforcement for millions of users worldwide, offering tools for URL categorization and real-time content analysis. Typically deployed in networks to ensure compliance with internet usage policies and to protect users from exposure to unsuitable content.

Cross-Site Scripting (XSS) is a security vulnerability that allows an attacker to inject malicious scripts into web pages viewed by other users. The scripts are executed in the context of the end-user’s browser, which can lead to several types of attacks including session hijacking and data theft. The attacker can steal cookies, session tokens, or other sensitive information retained by the browser and used with that site. XSS vulnerabilities can be present in web applications that fail to properly validate or escape user input. They pose a significant risk as they can escalate into unauthorized access to sensitive information and control over targeted user sessions.

In Netsweeper version 4.0.9, a Cross-Site Scripting (XSS) vulnerability was identified in one of its administrative scripts. The vulnerable endpoint can be exploited through fields like 'log', which directly reflects user input in the output without proper sanitation. By manipulating the 'log' parameter or similar fields, an attacker is capable of injecting arbitrary JavaScript into a user's web session. If successful, this script could execute within the user's browser in the security context of the affected domain. The vulnerability stems from inadequate input filtering and output encoding mechanisms while rendering controlled web content.

If exploited, this XSS vulnerability could allow attackers to execute arbitrary scripts on clients browsing the application. As a result, an attacker could steal cookies and sensitive session information, leading to session hijacking. The attacker could impersonate the legitimate user in the application or inject misleading content. Additionally, successful exploitation might provide a foothold for further attacks on users interacting with the application, compromising browser trust. It undermines the integrity of web content being displayed, potentially manipulating end-user perceptions or tracking their activities.

REFERENCES

• https://packetstormsecurity.com/files/download/133034/netsweeper-issues.tgz
• https://www.exploit-db.com/exploits/37930