JavaMelody Cross-Site Scripting Scanner

JavaMelody is a monitoring tool commonly used in Java applications to analyze and measure the performance of production environments. It is utilized by developers and system administrators to keep track of application statistics such as memory consumption, CPU usage, and database queries. JavaMelody helps in optimizing application performance by providing real-time data and historical graphs. The tool is often integrated into web applications to provide an insights dashboard. It assists organizations in maintaining the health and efficiency of their applications over time. JavaMelody is appreciated for its ability to deliver detailed monitoring without intrusiveness.

Cross-Site Scripting (XSS) is a vulnerability that allows an attacker to inject malicious scripts into web pages viewed by other users. When the injected script is executed in the user’s browser, it can be used to steal cookie-based authentication credentials or perform other malicious activities. XSS is typically found in web applications and can occur when input from an untrusted source is included in the output generated by the application. Different types of XSS attacks include stored, reflected, and DOM-based XSS. The impact of an XSS vulnerability ranges from a minor nuisance to a significant security risk, potentially leading to unauthorized actions on behalf of the victim user.

The specific endpoint in JavaMelody vulnerable to XSS involves the monitoring parameter that allows script execution. The vulnerability is exploited by injecting a script tag through the parameter, leading to arbitrary JavaScript execution. This occurs in the 'usedMemory' graph parameter, where scripts are not adequately sanitized. Successful exploitation means executing alert messages or other malicious scripts in the context of the victim’s browser. The vulnerability allows the execution of scripts within the application domain, which can result in unauthorized data access or manipulation. Attackers may use this vulnerability to gain deeper access into the affected systems by capturing authentication tokens or session cookies.

When exploited, XSS vulnerabilities like the one in JavaMelody can have several severe effects. Attackers may hijack user sessions, deface websites, or redirect users to malicious sites. They can steal sensitive information like usernames and passwords stored in cookies or other sensitive data accessible through client-side scripts. This could escalate into further attacks, such as malware distribution, phishing schemes, or more complex injections into the network. Persistent XSS attacks entice the attacker to target administrative users to take control of the application or the underlying servers. The efficacy of these attacks heavily depends on the specific context and privileges of the captured sessions.

REFERENCES

• https://github.com/Hurdano/JavaMelody-XSS
• https://github.com/javamelody/javamelody/pull/555