DeepSeek AI rXSS POC: A Practical Guide to Reflected Cross-Site Scripting

2025-02-04

Reflected Cross-Site Scripting (rXSS) is a common web vulnerability that occurs when an application includes unvalidated and unescaped user input in its output. This allows attackers to inject malicious scripts into web pages viewed by other users. In this article, we’ll explore a Proof of Concept (POC) for rXSS using DeepSeek AI and provide practical commands and code snippets to test and mitigate this vulnerability.

Understanding rXSS

Reflected XSS occurs when user input is immediately returned by the web application in an error message, search result, or any other response that includes some or all of the input provided by the user. Unlike stored XSS, the malicious script is not permanently stored on the server but is reflected back to the user in real-time.

DeepSeek AI rXSS POC

To demonstrate rXSS, let’s simulate a vulnerable web application and exploit it using DeepSeek AI. Below is a simple Python Flask application that is vulnerable to rXSS:

from flask import Flask, request, render_template_string

app = Flask(<strong>name</strong>)

@app.route('/search')
def search():
query = request.args.get('q', '')
return render_template_string(f'

<h1>Search Results for: {query}</h1>

')

if <strong>name</strong> == '<strong>main</strong>':
app.run(debug=True)

In this example, the application takes a user input (q) and directly embeds it into the HTML response without any sanitization. This makes it vulnerable to rXSS.

Exploiting rXSS

To exploit this vulnerability, an attacker can craft a URL that includes a malicious script. For example:

http://localhost:5000/search?q=<script>alert('XSS')</script>

When a user visits this URL, the script `alert(‘XSS’)` will be executed in their browser.

Mitigating rXSS

To prevent rXSS, always sanitize and escape user input before including it in the output. Here’s how you can modify the Flask application to mitigate the vulnerability:

from flask import Flask, request, render_template_string, escape

app = Flask(<strong>name</strong>)

@app.route('/search')
def search():
query = request.args.get('q', '')
safe_query = escape(query) # Escaping user input
return render_template_string(f'

<h1>Search Results for: {safe_query}</h1>

')

if <strong>name</strong> == '<strong>main</strong>':
app.run(debug=True)

By using the `escape` function, any HTML or JavaScript in the user input will be rendered harmless.

Testing for rXSS

You can use tools like `OWASP ZAP` or `Burp Suite` to automate the detection of rXSS vulnerabilities. Here’s a simple command to run a basic scan using OWASP ZAP:

zap-cli quick-scan --spider --ajax-spider --recursive http://localhost:5000

Conclusion: What Undercode Say

Reflected Cross-Site Scripting (rXSS) remains a significant threat to web applications, allowing attackers to execute malicious scripts in the context of a victim’s browser. Understanding how to exploit and mitigate rXSS is crucial for cybersecurity professionals. Below are some additional Linux commands and tools that can help you in your journey to secure web applications:

Nikto: A web server scanner that tests for dangerous files, outdated server software, and other vulnerabilities.
```
nikto -h http://localhost:5000
```
Nmap: A network scanning tool that can be used to discover open ports and services.
```
nmap -sV -p 5000 localhost
```
SQLMap: A tool that automates the process of detecting and exploiting SQL injection flaws.
```
sqlmap -u "http://localhost:5000/search?q=1" --dbs
```
Wfuzz: A web application brute-forcing tool that can be used to fuzz parameters and discover vulnerabilities.
```
wfuzz -c -z range,1-100 http://localhost:5000/search?q=FUZZ
```
Lynis: A security auditing tool for Unix/Linux systems.
```
lynis audit system
```

6. Gobuster: A directory/file brute-forcing tool.

gobuster dir -u http://localhost:5000 -w /path/to/wordlist.txt

Metasploit: A penetration testing framework that can be used to exploit vulnerabilities.
```
msfconsole
```

Curl: A command-line tool to transfer data from or to a server.

curl -X GET "http://localhost:5000/search?q=<script>alert('XSS')</script>"

Wget: A command-line utility for downloading files from the web.

wget http://localhost:5000/search?q=<script>alert('XSS')</script>

Docker: A platform for developing, shipping, and running applications in containers.
```
docker run -d -p 5000:5000 my-flask-app
```

By incorporating these tools and commands into your cybersecurity practices, you can better defend against rXSS and other web vulnerabilities. Always remember to sanitize user input, use secure coding practices, and regularly test your applications for vulnerabilities.

For further reading, check out the following resources:

References:

Hackers Feeds, Undercode AI