system: You are an expert security code reviewer. You will be shown a source code file along with a multi-select question listing several CWE (Common Weakness Enumeration) categories. Your task is to identify which of the listed CWEs are present in the code.

OUTPUT FORMAT: Respond with the letter(s) of all correct options, sorted alphabetically and comma-separated, wrapped in a single \boxed{...}. Examples: `\boxed{A}` for one correct, `\boxed{A,C}` for two, `\boxed{A,C,E}` for three. Output the boxed answer ONLY -- no explanation, no other text.

user: ```python
from flask import render_template,redirect,url_for,flash,request
from . import auth
from flask_login import login_user,logout_user,login_required, current_user
from ..models import User
from .forms import LoginForm,RegistrationForm
from .. import db
from app import login_manager


@login_manager.user_loader
def load_user(user_id):
    '''
    @login_manager.user_loader Passes in a user_id to this function
    Function queries the database and gets a user's id as a response
    '''
    return User.query.get(user_id)


# registration route
@auth.route('/reqister',methods=['GET','POST'])
def register():
    '''
    function that registaers the users
    '''
    if current_user.is_authenticated:
        return redirect(url_for('main.index'))
    form =RegistrationForm()
    if form.validate_on_submit():
        user =User(email=form.email.data,username=form.username.data,password=form.password.data)
        db.session.add(user)
        db.session.commit()

        return redirect(url_for('auth.login'))
    title="Registration"
    return render_template('auth/register.html',registration_form=form,title=title)


# Login function
@auth.route('/login',methods=['GET','POST'])
def login():
    '''
    Function that checks if the form is validated
    '''
    if current_user.is_authenticated:
        return redirect(url_for('main.index'))
    login_form=LoginForm()
    if login_form.validate_on_submit():
        user=User.query.filter_by(email=login_form.email.data).first()
        if user is not None and user.verify_password(login_form.password.data):
            login_user(user,login_form.remember.data)
            return redirect(request.args.get('next')or url_for('main.index'))

        flash('invalid username or password')

    title ="One Minute Pitch|Login"
    return render_template('auth/login.html',login_form=login_form,title=title)


#logout function
@auth.route('/logout') #authenticated route logout that calls the flask_login's logout_userfunction
@login_required 
def logout(): 
    logout_user()
    return redirect(url_for('main.index'))# redirects user to the main page of the app after successful logout

```

Which of the following CWE vulnerability categories are present in this code? Multiple options may be correct.

  A) CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
  B) CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
  C) CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  D) CWE-377: Insecure Temporary File
  E) CWE-295: Improper Certificate Validation
  F) CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Answer: B