Django + DRF: 403 FORBIDDEN: CSRF token missing or incorrect

I have an Android client app that tries to authenticate with a Django + DRF backend. However, when I try to login, I get the following response:

403: CSRF Failed: CSRF token missing or incorrect.

The request is sent to http://localhost/rest-auth/google/ with the following body:

access_token: <the OAuth token from Google>

What could cause this? The client doesn't have a CSRF token since the POST to authenticate is the first thing to happen between the client and the server. I checked out a lot of the past questions with the same problem, but I couldn't find any solutions.

The relevant settings on the Django side are like this:

AUTHENTICATION_BACKENDS = (
    "django.contrib.auth.backends.ModelBackend",
    "allauth.account.auth_backends.AuthenticationBackend"
)

TEMPLATE_CONTEXT_PROCESSORS = (
    "django.core.context_processors.request",
    "django.contrib.auth.context_processors.auth",
    "allauth.account.context_processors.account",
    "allauth.socialaccount.context_processors.socialaccount"
)

MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
)

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'app',
    'allauth',
    'allauth.account',
    'allauth.socialaccount',
    'allauth.socialaccount.providers.facebook',
    'allauth.socialaccount.providers.google',

    'django.contrib.admin',

    # REST framework
    'rest_framework',
    'rest_framework.authtoken',
    'rest_auth',
    'rest_auth.registration',
)

REST_FRAMEWORK = {
    'DEFAULT_PERMISSION_CLASSES': ( 
        'rest_framework.permissions.IsAuthenticated'
    ),
}

Silly me, I missed the TokenAuthentication framework from the REST settings:

settings.py

REST_FRAMEWORK = {
    'DEFAULT_AUTHENTICATION_CLASSES': (
        'rest_framework.authentication.TokenAuthentication',
    )
}

Now it works just as intended.