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 fastapi import APIRouter, Query, HTTPException
from typing import Optional
from pydantic import ValidationError
from .models import InsuranceModel, UserModel
from app import controller
from fastapi.responses import JSONResponse
from app.config import settings
import requests
import json
import logging

logger = logging.getLogger(__name__)

router = APIRouter()


def get_api_results(url, id):
    """[summary]

    Args:
        url ([str]): [External API url]
        id ([int]): [member id]

    Returns:
        [json]: [API request response]
    """
    r = requests.get(url.format(id))
    return r.json()


@router.get("/", tags=["root"])
async def read_root():
    """[Root endpoint]

    Returns:
        [json]: [Welcome snippet]
    """
    return {'Hello': 'Challenge'}


@router.get("/insurance/", tags=["insurance"], response_model=UserModel)
async def get_insurance(id: int, method: Optional[str] = Query('most_repeated_values')):
    """[summary]

    Args:
        id (int): [member id]
        method (Optional[str], optional): [selector for calculation method]. Defaults to Query('most_repeated_values').

    Raises:
        HTTPException: [API values validation]

    Returns:
        [user object]: [user objet with results]
    """

    from .mock_api import data

    if method == 'most_repeated_values' or method == 'average_values':
        pass
    else:
        return JSONResponse(content='Enter valid calculation method')

    f = getattr(controller, method)

    results = []
    responses = []
    errors = []

    try:
        for url in settings.URLS:
            responses.append(get_api_results(url, id))
    except:
        responses = [b for a in data if a['member_id'] == id for \
            b in a['responses']]

    for url, response in zip(settings.URLS, responses):
        try:
            results.append(InsuranceModel(api=url.split('?')[0], **response))
        except ValueError as e:
            errors.append(json.loads(e.json())[0])
    if errors:
        raise HTTPException(status_code=400, detail=errors)

    true_deductible, true_stop_loss, true_oop_max = f(responses)

    member = UserModel(id=id,
                       true_deductible=true_deductible,
                       true_stop_loss=true_stop_loss,
                       true_oop_max=true_oop_max,
                       insurance_data=results
                       )

    return member

```

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

  A) CWE-730: OWASP Top Ten 2004 Category A9 - Denial of Service
  B) CWE-295: Improper Certificate Validation
  C) CWE-918: Server-Side Request Forgery (SSRF)
  D) CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
  E) CWE-116: Improper Encoding or Escaping of Output
  F) CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')
Answer: C