Nuxt.js Cross-Site Scripting (XSS) Scanner

Nuxt.js is a popular framework used in building server-side rendered applications, often utilized by developers seeking to streamline their web application projects. It is commonly used by software engineers and web developers for efficient rendering, offering both client-side and server-side configurations. Nuxt.js aids in creating dynamic and static websites with speed and functionality, making it prominent among developers optimizing for Vue.js applications. This framework enhances application scalability and maintenance, providing an ecosystem that simplifies development tasks. Its modular architecture allows easy integration with other libraries to extend functionalities, making it a powerful tool for rapidly deploying modern web applications. Organizations use Nuxt.js to improve SEO, develop responsive web apps, and ensure fast rendering times, accommodating both small teams and enterprise-level solutions.

The vulnerability targeted by the scanner involves Cross-Site Scripting (XSS), a prevalent risk in many web applications. XSS vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users, leading to unauthorized operations within browser contexts. This type of flaw arises when applications fail to ensure the safe rendering of server-generated content, allowing attackers to manipulate the document structure or fetch sensitive user data. In the context of Nuxt.js, unsafely rendered stack traces can lead to scripts executing within the app's error pages, introducing significant security risks. Due to this flaw, an adversary can manipulate the application to perform unintended actions, potentially compromising both user data and the underlying system. Identifying and mitigating these flaws is crucial to preserving the integrity and security of Nuxt.js apps.

This vulnerability specifically involves the error handling pages of Nuxt.js, where stack traces in error responses are displayed without proper sanitization. The insecure rendering of stack traces opens a vector for injecting scripts via malformed requests. Users encountering the error page with injected scripts can unknowingly execute malicious code, leading to security breaches. The payload used in the template sends a '<script>alert(document.domain)</script>' within a stack parameter, which is not safely rendered, leading to script execution. The detected condition confirms successful exploitation by checking if the crafted payload is reflected in the body and header content of the error response. By addressing this flaw, developers can better secure applications against unauthorized script injections.

Exploiting this vulnerability could result in multiple adverse effects, affecting both users and application security. Successful exploitation allows attackers to execute unauthorized scripts in the context of the victim's session, potentially gaining access to sensitive data such as cookies, session tokens, and user credentials. This can lead to session hijacking, unauthorized actions performed in the name of legitimate users, and information disclosure. Attackers may further leverage this flaw to spread malware, deface web pages, or engage in phishing attacks targeting application users. Proactive mitigation of XSS vulnerabilities is essential to protect user confidentiality, integrity, and the availability of application services. To counteract this risk, robust input validation and content sanitization measures should be applied, with appropriate error handling and secure rendering practices.

REFERENCES

• https://huntr.dev/bounties/70ac720d-c932-4ed3-98b1-dd2cbcb90185/
• https://bryces.io/blog/nuxt3
• https://twitter.com/fofabot/status/1669339995780558849