diff --git a/connexion/json_schema.py b/connexion/json_schema.py
index 2e7500501..ec1832342 100644
--- a/connexion/json_schema.py
+++ b/connexion/json_schema.py
@@ -2,21 +2,70 @@
 Module containing all code related to json schema validation.
 """
 
+import contextlib
+import io
+import os
 import typing as t
+import urllib.parse
+import urllib.request
 from collections.abc import Mapping
 from copy import deepcopy
 
+import requests
+import yaml
 from jsonschema import Draft4Validator, RefResolver
 from jsonschema.exceptions import RefResolutionError, ValidationError  # noqa
 from jsonschema.validators import extend
-from openapi_spec_validator.handlers import UrlHandler
 
 from .utils import deep_get
 
+
+class ExtendedSafeLoader(yaml.SafeLoader):
+    """Extends the yaml SafeLoader to coerce all keys to string so the result is valid json."""
+
+    def __init__(self, stream):
+        self.original_construct_mapping = self.construct_mapping
+        self.construct_mapping = self.extended_construct_mapping
+        super().__init__(stream)
+
+    def extended_construct_mapping(self, node, deep=False):
+        data = self.original_construct_mapping(node, deep)
+        return {str(key): data[key] for key in data}
+
+
+class FileHandler:
+    """Handler to resolve file refs."""
+
+    def __call__(self, uri):
+        filepath = self._uri_to_path(uri)
+        with open(filepath) as fh:
+            return yaml.load(fh, ExtendedSafeLoader)
+
+    @staticmethod
+    def _uri_to_path(uri):
+        parsed = urllib.parse.urlparse(uri)
+        host = "{0}{0}{mnt}{0}".format(os.path.sep, mnt=parsed.netloc)
+        return os.path.abspath(
+            os.path.join(host, urllib.request.url2pathname(parsed.path))
+        )
+
+
+class URLHandler:
+    """Handler to resolve url refs."""
+
+    def __call__(self, uri):
+        response = requests.get(uri)
+        response.raise_for_status()
+
+        data = io.StringIO(response.text)
+        with contextlib.closing(data) as fh:
+            return yaml.load(fh, ExtendedSafeLoader)
+
+
 default_handlers = {
-    'http': UrlHandler('http'),
-    'https': UrlHandler('https'),
-    'file': UrlHandler('file'),
+    'http': URLHandler(),
+    'https': URLHandler(),
+    'file': FileHandler(),
 }
 
 
diff --git a/setup.py b/setup.py
index c5d174922..c85f017d0 100755
--- a/setup.py
+++ b/setup.py
@@ -25,7 +25,6 @@ def read_version(package):
     'PyYAML>=5.1,<6',
     'requests>=2.9.1,<3',
     'inflection>=0.3.1,<0.6',
-    'openapi-spec-validator>=0.2.4,<0.4',
     'werkzeug>=1.0,<3',
 ]
 
diff --git a/tests/api/test_bootstrap.py b/tests/api/test_bootstrap.py
index da22d56e2..4ad3b4586 100644
--- a/tests/api/test_bootstrap.py
+++ b/tests/api/test_bootstrap.py
@@ -7,7 +7,7 @@
 from connexion import App
 from connexion.exceptions import InvalidSpecification
 from connexion.http_facts import METHODS
-from openapi_spec_validator.loaders import ExtendedSafeLoader
+from connexion.json_schema import ExtendedSafeLoader
 
 from conftest import TEST_FOLDER, build_app_from_fixture