[Security] Fix hardcoded Django SECRET_KEY with environment variable (CWE-798)

[saaa99999999]

Security Audit Report ??Lithium (wsvincent/lithium)

Manual code audit discovered 1 critical security vulnerability ??CWE-798: Hardcoded Django SECRET_KEY.

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CRITICAL: CWE-798 ??Hardcoded Django SECRET_KEY Published in Public Repository (CVSS 9.1)

Location: django_project/settings.py:12

Data Flow:

django_project/settings.py:12 SECRET_KEY = "django-insecure-0peo@#x9jur3!h$ryje!$879xww8y1y66jx!%*#ymhg&jkozs2"
  ??Django's cryptographic signing (django.core.signing.Signer)
  ??Session cookie signing ??django.contrib.sessions
  ??CSRF token generation ??django.middleware.csrf
  ??Password reset tokens ??django.contrib.auth.tokens.PasswordResetTokenGenerator
  ??Any SignedData/JSON signing within Django

Description:
The Django SECRET_KEY is the root of trust for all cryptographic operations in Django. The settings.py file contained a hardcoded key with the django-insecure- prefix ??this is the exact format Django's startproject command generates with the explicit warning "This key is insecure and should not be used in production."

The key was published in the public GitHub repository at wsvincent/lithium (previously djangox). Anyone who views the repository can:

1. Forge session cookies ??Django uses SECRET_KEY for signing session data. An attacker can create a valid session cookie for any user, bypassing authentication entirely.
2. Generate valid CSRF tokens ??CSRF protection is defeated.
3. Forge password reset tokens ??The password reset flow uses SECRET_KEY to sign tokens. An attacker can generate valid reset links for any email.
4. Tamper with any SignedData ??Any use of Django's signing API is compromised.

The key has the django-insecure- prefix which Django 5.2+ specifically identifies and warns about. Django will emit system check warnings (security.W009) for keys with this prefix.

Proof of Concept (session forgery):

from django.core.signing import Signer
from django.core.serializers.json import DjangoJSONEncoder
import json

SECRET_KEY = "django-insecure-0peo@#x9jur3!h$ryje!$879xww8y1y66jx!%*#ymhg&jkozs2"
signer = Signer(key=SECRET_KEY, salt="django.contrib.sessions.backends.signed_cookies")

# Forge a session cookie for user ID 1 (typically the admin)
session_data = {"_auth_user_id": "1", "_auth_user_backend": "django.contrib.auth.backends.ModelBackend"}
signed = signer.sign(json.dumps(session_data, cls=DjangoJSONEncoder))
print(f"Set-Cookie: sessionid={signed}")

Proof of Concept (password reset token):

from django.contrib.auth.tokens import PasswordResetTokenGenerator
from django.conf import settings
settings.configure(SECRET_KEY=SECRET_KEY)

token_gen = PasswordResetTokenGenerator()
token = token_gen.make_token(user)  # where user.pk=1
reset_url = f"http://localhost:8000/accounts/password/reset/key/{user.pk}-{token}/"
# Use this URL to reset any user's password without email access

Fix:

1. django_project/settings.py:12-17: Replaced hardcoded SECRET_KEY with os.environ.get("DJANGO_SECRET_KEY", "") and added startup validation that throws ValueError if the key is empty or uses the django-insecure- prefix.
2. .env.example: Added with documentation and key generation instructions (python -c "import secrets; print(secrets.token_urlsafe(50))").

Before ??After:

django_project/settings.py:12:

# Before:
SECRET_KEY = "django-insecure-0peo@#x9jur3!h$ryje!$879xww8y1y66jx!%*#ymhg&jkozs2"

# After:
SECRET_KEY = os.environ.get("DJANGO_SECRET_KEY", "")

if not SECRET_KEY or SECRET_KEY.startswith("django-insecure-"):
    raise ValueError(
        "DJANGO_SECRET_KEY environment variable is not set or uses an insecure default. "
        'Generate a secure key: python -c "import secrets; print(secrets.token_urlsafe(50))"'
    )

django_project/settings.py:19:

# Before:
DEBUG = True

# After:
DEBUG = os.environ.get("DJANGO_DEBUG", "False").lower() in ("true", "1")

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Changes in this PR (2 files)

File	Change
django_project/settings.py	Replaced hardcoded SECRET_KEY with DJANGO_SECRET_KEY env var + startup validation; Made DEBUG configurable via DJANGO_DEBUG env var
.env.example	Added with DJANGO_SECRET_KEY and DJANGO_DEBUG documentation

CVSS 3.1 Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N ??9.1 (Critical)

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Manual security audit of Django settings and key management

[saaa99999999]

CVE Request — Action Needed from Maintainer

This PR fixes security vulnerabilities. To assign a CVE number:

GitHub only issues CVEs from the official upstream repository, not from forks.

Please:

1. Go to this repo → Security → Advisories → New draft security advisory
2. Add @saaa99999999 as a collaborator
3. I will populate the full vulnerability details (CVSS, CWE, data flow, PoC) and submit the CVE request

If you prefer, I can submit the CVE via MITRE (cveform.mitre.org) instead — just let me know.

Thank you for reviewing this PR!