Beyond Session Hijacking: Using JavaScript Libraries for Comprehensive User Profiling Through XSS

• Cross-Site Scripting (XSS) attacks are often associated with stealing cookies or session tokens, but their potential extends far beyond these common objectives.

• By leveraging JavaScript libraries, attackers can gather a wealth of data, creating detailed profiles of users that go well beyond traditional session hijacking.

Impact

Privacy Invasion

• One of the most immediate implications of advanced XSS profiling is the invasion of user privacy.

• Traditional XSS attacks typically focus on stealing session cookies, but with profiling techniques, attackers can collect:

  • Personal Information: Data such as IP address, time zone, and language settings can be correlated with other information to infer the user’s geographic location and potentially expose their identity.

  • Browser and Device Fingerprinting: By creating a unique fingerprint based on the user's browser, operating system, and hardware configurations, attackers can track users across multiple sites and sessions. This type of tracking is persistent and difficult for users to detect or prevent, even if they regularly clear cookies or use privacy-focused browsers.

  • Behavioral Data: Monitoring how users interact with websites, such as their navigation patterns, click behavior, and typing speed, can provide insights into their habits and preferences. This data can be used to build detailed profiles that may be sold to advertisers or exploited for malicious purposes.

Targeted Exploits and Attacks

• With detailed information gathered through advanced XSS profiling, attackers can craft highly targeted exploits:

  • Customized Phishing Attacks: Knowledge of the user’s environment allows attackers to design phishing emails or malicious websites that mimic the user’s known platforms, increasing the likelihood of a successful attack.

  • Exploiting Specific Vulnerabilities: If an attacker knows the exact browser version, operating system, or installed plugins, they can target vulnerabilities specific to that environment. This increases the chances of bypassing security defenses and successfully compromising the system.

  • Social Engineering: Detailed user profiles can be used to inform social engineering tactics, making them more convincing and harder to detect. For instance, an attacker might craft a message that references specific details about the user’s device or network, lending credibility to their malicious intent.

Long-Term Tracking and Surveillance

• One of the more insidious implications of advanced XSS profiling is the ability to track users over an extended period:

  • Persistent User Tracking: Even in the absence of cookies, fingerprinting techniques can enable long-term tracking. Attackers can monitor a user’s activities across multiple websites and sessions, building a comprehensive history of their online behavior.

  • Profiling Across Devices: Advanced profiling can sometimes distinguish between different devices used by the same person, allowing attackers to track a user's activities across their desktop, mobile phone, and tablet. This creates a multi-dimensional profile that offers more opportunities for targeted attacks.

  • Surveillance and Monitoring: In a more extreme scenario, the data gathered through XSS profiling could be used for surveillance purposes. Whether by state actors, criminal organizations, or unethical businesses, the ability to monitor a user’s online actions over time poses a significant threat to personal freedom and security.

Compromising Organizational Security

• When applied in a corporate context, the implications of advanced XSS profiling extend beyond individual users to entire organizations:

  • Identifying Key Personnel: Attackers can use profiling to identify high-value targets within an organization, such as executives, IT administrators, or finance officers. These individuals often have access to sensitive information and systems, making them prime targets for further exploitation.

  • Mapping the Organizational Network: By profiling users within an organization, attackers can gather information about the internal network, including browser versions, operating systems, and the types of devices in use. This information can be used to plan broader attacks, such as network infiltration or the deployment of malware.

  • Supply Chain Attacks: Attackers could use the information obtained from XSS profiling to target third-party vendors or partners that interact with the organization, leading to supply chain attacks that can compromise the entire business ecosystem.

Profiling Users with JavaScript Libraries

uaparser.js

• uaparser.js parses user-agent strings to extract detailed information about the user's browser, operating system, and device. When used in an XSS attack, this library can help attackers identify:

  • Browser Information: Type, version, and rendering engine.

  • Operating System: Name, version, and platform.

  • Device: Type (mobile, tablet, desktop), model, and manufacturer.

FingerprintJS

• FingerprintJS generates a unique identifier for a user's device based on various browser and device attributes.

  • Fingerprint Identification is 99.5% (FingerprintJS claim)

• This technique allows attackers to:

  • Create Unique Identifiers: Track users across sessions even without cookies.

  • Gather Detailed Information: Screen resolution, installed plugins, time zone, language, and more.

ClientJS

• ClientJS collects a wide range of data points about the user’s environment, including:

  • Hardware Information: Details about the CPU, GPU, and available memory.

  • Network Information: Data about the user’s IP address, connection type, and more.

  • Behavioral Data: Information on how users interact with the site, which can be used to profile their behaviour.

Code

• not the complete code

<script src="https://cdn.jsdelivr.net/npm/ua-parser-js/dist/ua-parser.min.js"></script>

<script>

  

console.log("*************************");

const uap = new UAParser();

console.log(uap.getResult());

const parser = new UAParser(uap);

  

console.log(parser.getBrowser());

console.log(parser.getEngine());

console.log(parser.getDevice());

console.log(parser.getOS());

console.log(parser.getCPU());

console.log(parser.getDevice());

console.log(parser.getEngine());

console.log(parser.getResult());

  

</script>

References

• uaparser.js
• FingerprintJS

  • https://fingerprintjs.github.io/fingerprintjs/

• ClientJS