Privilege Escalation in Django with Cockroachdb

Privilege escalation occurs when an attacker gains elevated access beyond what their identity or role permits. In a Django application using CockroachDB, the risk often arises from a mismatch between Django’s permission checks and how database roles and ownership are configured in CockroachDB. Unlike single-node PostgreSQL, CockroachDB is a distributed SQL system with its own identity and privilege model (SQL roles, GRANT/REVOKE on databases, tables, and schemas). If Django’s database user is over-privileged in CockroachDB, an attacker who exploits a logic flaw (e.g., Insecure Direct Object References or IDOR) can issue statements that modify or read data they should not access.

Specifically, Django’s default database user might be granted CREATEDB or other administrative rights during initial CockroachDB setup for convenience. In production, this broad access persists, and if a vulnerability such as BOLA (Broken Level Authorization) exists in an API endpoint that constructs dynamic SQL or uses the Django ORM with insufficient row-level checks, an attacker can manipulate object identifiers to act as another user. Because CockroachDB respects the connected role’s privileges, Django’s ORM will execute queries with those elevated rights, enabling unauthorized data export, data modification, or even schema changes. Additionally, CockroachDB’s multi-region capabilities and secondary indexes can inadvertently expose data through misconfigured zone configurations or backup restores that do not enforce the same role restrictions, compounding privilege escalation paths.

Another vector involves Django’s session store or caching layer pointing to CockroachDB. If session tables are accessible to a low-privilege application user but the database user has broader access, an attacker can manipulate session tokens to escalate privileges. The ORM’s use of raw SQL or querysets with extra() or raw() can bypass Django’s permission checks if inputs are not strictly validated, and CockroachDB will execute those statements with the connection user’s rights. Real-world attack patterns such as OWASP API Top 10 #1 Broken Object Level Authorization map directly here: insufficient checks on object ownership allow horizontal or vertical privilege escalation when the backend identity in CockroachDB is overly permissive.

Remediation focuses on least-privilege database roles, strict ownership, and safe ORM usage. In CockroachDB, create a dedicated role for Django that matches the minimum required permissions. Avoid using the root or a highly privileged role for routine operations. Use GRANT to assign only SELECT, INSERT, UPDATE, DELETE on specific tables and schemas. For Django migrations, use a separate, temporarily elevated role or run migrations outside the application runtime with a role that has DDL rights, then revert to the low-privilege role for runtime connections.

Ensure that all querysets and raw SQL are parameterized and avoid constructing SQL with string interpolation. Use Django’s built-in protections like select_related and prefetch_related to minimize the need for raw SQL. When raw SQL is unavoidable, use params= to pass values safely. Below are concrete CockroachDB SQL examples and Django settings to enforce least privilege and prevent privilege escalation.

1. Create a least-privilege CockroachDB role for Django

-- In CockroachDB, create a role with minimal rights
CREATE ROLE django_app WITH LOGIN PASSWORD 'strong_password';
GRANT CONNECT ON DATABASE your_db TO django_app;
GRANT USAGE ON SCHEMA public TO django_app;
-- Grant only necessary table privileges
GRANT SELECT, INSERT, UPDATE, DELETE ON TABLE public.auth_user TO django_app;
GRANT SELECT, INSERT, UPDATE, DELETE ON TABLE public.auth_session TO django_app;
-- Explicitly deny dangerous actions
REVOKE ALL ON DATABASE your_db FROM django_app;

2. Django DATABASES settings referencing the role

# settings.py
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': 'your_db',
        'USER': 'django_app',
        'PASSWORD': 'strong_password',
        'HOST': 'your-cockroachdb-host',
        'PORT': '26257',
        'OPTIONS': {
            'sslmode': 'require',
        },
    }
}

3. Parameterized queries and safe ORM usage

# Safe: using queryset filter with parameter, not string interpolation
user = User.objects.filter(pk=request.GET.get('id')).first()

# If raw SQL is necessary, use params to avoid injection and respect role limits
from django.db import connection
with connection.cursor() as cursor:
    cursor.execute(
        'SELECT data FROM audit_log WHERE user_id = %s AND created_at > %s',
        [user_id, start_date]
    )
    rows = cursor.fetchall()

4. Migrations with a separate role

Run migrations using a higher-privilege role, then switch back to the low-privilege role for the app. Example psql commands:

-- Apply migrations as a migration role
GRANT ALL ON DATABASE your_db TO migration_role;
-- Use migration_role for Django migrate
# DATABASE_URL=postgresql://migration_role:pass@host:26257/your_db python manage.py migrate
-- Revoke after migration
REVOKE ALL ON DATABASE your_db FROM migration_role;

5. Session and caching considerations

Configure Django to use a dedicated schema or table for sessions and ensure the django_app role has only the rights needed. Avoid storing sensitive data in client-side sessions and validate ownership on every request.

6. Monitoring and testing

Use the Django debug toolbar and CockroachDB’s statement logging to verify that the application role does not attempt unauthorized operations. Regularly review GRANTs to ensure they remain minimal.