diff --git a/modules/openapi-generator/src/main/resources/python/asyncio/rest.mustache b/modules/openapi-generator/src/main/resources/python/asyncio/rest.mustache
index 3b201d99ba9..937e76ed5a4 100644
--- a/modules/openapi-generator/src/main/resources/python/asyncio/rest.mustache
+++ b/modules/openapi-generator/src/main/resources/python/asyncio/rest.mustache
@@ -47,7 +47,8 @@ class RESTClientObject:
         self.maxsize = configuration.connection_pool_maxsize
 
         self.ssl_context = ssl.create_default_context(
-            cafile=configuration.ssl_ca_cert
+            cafile=configuration.ssl_ca_cert,
+            cadata=configuration.ca_cert_data,
         )
         if configuration.cert_file:
             self.ssl_context.load_cert_chain(
diff --git a/modules/openapi-generator/src/main/resources/python/configuration.mustache b/modules/openapi-generator/src/main/resources/python/configuration.mustache
index 667a5c88fc9..0dca8be3583 100644
--- a/modules/openapi-generator/src/main/resources/python/configuration.mustache
+++ b/modules/openapi-generator/src/main/resources/python/configuration.mustache
@@ -10,7 +10,7 @@ from logging import FileHandler
 import multiprocessing
 {{/asyncio}}
 import sys
-from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict
+from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict, Union
 from typing_extensions import NotRequired, Self
 
 import urllib3
@@ -183,6 +183,8 @@ class Configuration:
     :param ssl_ca_cert: str - the path to a file of concatenated CA certificates
       in PEM format.
     :param retries: Number of retries for API requests.
+    :param ca_cert_data: verify the peer using concatenated CA certificate data
+      in PEM (str) or DER (bytes) format.
 
 {{#hasAuthMethods}}
     :Example:
@@ -282,13 +284,14 @@ conf = {{{packageName}}}.Configuration(
 {{#hasHttpSignatureMethods}}
         signing_info: Optional[HttpSigningConfiguration]=None,
 {{/hasHttpSignatureMethods}}
-        server_index: Optional[int]=None, 
+        server_index: Optional[int]=None,
         server_variables: Optional[ServerVariablesT]=None,
         server_operation_index: Optional[Dict[int, int]]=None,
         server_operation_variables: Optional[Dict[int, ServerVariablesT]]=None,
         ignore_operation_servers: bool=False,
         ssl_ca_cert: Optional[str]=None,
         retries: Optional[int] = None,
+        ca_cert_data: Optional[Union[str, bytes]] = None,
         *,
         debug: Optional[bool] = None,
     ) -> None:
@@ -373,6 +376,10 @@ conf = {{{packageName}}}.Configuration(
         self.ssl_ca_cert = ssl_ca_cert
         """Set this to customize the certificate file to verify the peer.
         """
+        self.ca_cert_data = ca_cert_data
+        """Set this to verify the peer using PEM (str) or DER (bytes)
+           certificate data.
+        """
         self.cert_file = None
         """client certificate file
         """
diff --git a/modules/openapi-generator/src/main/resources/python/rest.mustache b/modules/openapi-generator/src/main/resources/python/rest.mustache
index fc71a59cf40..f545066bb67 100644
--- a/modules/openapi-generator/src/main/resources/python/rest.mustache
+++ b/modules/openapi-generator/src/main/resources/python/rest.mustache
@@ -66,6 +66,7 @@ class RESTClientObject:
             "ca_certs": configuration.ssl_ca_cert,
             "cert_file": configuration.cert_file,
             "key_file": configuration.key_file,
+            "ca_cert_data": configuration.ca_cert_data,
         }
         if configuration.assert_hostname is not None:
             pool_args['assert_hostname'] = (
diff --git a/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/configuration.py b/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/configuration.py
index e48902fd8ed..d1ae379ac7b 100644
--- a/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/configuration.py
+++ b/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/configuration.py
@@ -19,7 +19,7 @@ import logging
 from logging import FileHandler
 import multiprocessing
 import sys
-from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict
+from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict, Union
 from typing_extensions import NotRequired, Self
 
 import urllib3
@@ -163,6 +163,8 @@ class Configuration:
     :param ssl_ca_cert: str - the path to a file of concatenated CA certificates
       in PEM format.
     :param retries: Number of retries for API requests.
+    :param ca_cert_data: verify the peer using concatenated CA certificate data
+      in PEM (str) or DER (bytes) format.
 
     :Example:
 
@@ -193,13 +195,14 @@ conf = openapi_client.Configuration(
         username: Optional[str]=None,
         password: Optional[str]=None,
         access_token: Optional[str]=None,
-        server_index: Optional[int]=None, 
+        server_index: Optional[int]=None,
         server_variables: Optional[ServerVariablesT]=None,
         server_operation_index: Optional[Dict[int, int]]=None,
         server_operation_variables: Optional[Dict[int, ServerVariablesT]]=None,
         ignore_operation_servers: bool=False,
         ssl_ca_cert: Optional[str]=None,
         retries: Optional[int] = None,
+        ca_cert_data: Optional[Union[str, bytes]] = None,
         *,
         debug: Optional[bool] = None,
     ) -> None:
@@ -277,6 +280,10 @@ conf = openapi_client.Configuration(
         self.ssl_ca_cert = ssl_ca_cert
         """Set this to customize the certificate file to verify the peer.
         """
+        self.ca_cert_data = ca_cert_data
+        """Set this to verify the peer using PEM (str) or DER (bytes)
+           certificate data.
+        """
         self.cert_file = None
         """client certificate file
         """
diff --git a/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/rest.py b/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/rest.py
index 91fb8eb029d..89600d574a4 100644
--- a/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/rest.py
+++ b/samples/client/echo_api/python-disallowAdditionalPropertiesIfNotPresent/openapi_client/rest.py
@@ -77,6 +77,7 @@ class RESTClientObject:
             "ca_certs": configuration.ssl_ca_cert,
             "cert_file": configuration.cert_file,
             "key_file": configuration.key_file,
+            "ca_cert_data": configuration.ca_cert_data,
         }
         if configuration.assert_hostname is not None:
             pool_args['assert_hostname'] = (
diff --git a/samples/client/echo_api/python/openapi_client/configuration.py b/samples/client/echo_api/python/openapi_client/configuration.py
index e48902fd8ed..d1ae379ac7b 100644
--- a/samples/client/echo_api/python/openapi_client/configuration.py
+++ b/samples/client/echo_api/python/openapi_client/configuration.py
@@ -19,7 +19,7 @@ import logging
 from logging import FileHandler
 import multiprocessing
 import sys
-from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict
+from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict, Union
 from typing_extensions import NotRequired, Self
 
 import urllib3
@@ -163,6 +163,8 @@ class Configuration:
     :param ssl_ca_cert: str - the path to a file of concatenated CA certificates
       in PEM format.
     :param retries: Number of retries for API requests.
+    :param ca_cert_data: verify the peer using concatenated CA certificate data
+      in PEM (str) or DER (bytes) format.
 
     :Example:
 
@@ -193,13 +195,14 @@ conf = openapi_client.Configuration(
         username: Optional[str]=None,
         password: Optional[str]=None,
         access_token: Optional[str]=None,
-        server_index: Optional[int]=None, 
+        server_index: Optional[int]=None,
         server_variables: Optional[ServerVariablesT]=None,
         server_operation_index: Optional[Dict[int, int]]=None,
         server_operation_variables: Optional[Dict[int, ServerVariablesT]]=None,
         ignore_operation_servers: bool=False,
         ssl_ca_cert: Optional[str]=None,
         retries: Optional[int] = None,
+        ca_cert_data: Optional[Union[str, bytes]] = None,
         *,
         debug: Optional[bool] = None,
     ) -> None:
@@ -277,6 +280,10 @@ conf = openapi_client.Configuration(
         self.ssl_ca_cert = ssl_ca_cert
         """Set this to customize the certificate file to verify the peer.
         """
+        self.ca_cert_data = ca_cert_data
+        """Set this to verify the peer using PEM (str) or DER (bytes)
+           certificate data.
+        """
         self.cert_file = None
         """client certificate file
         """
diff --git a/samples/client/echo_api/python/openapi_client/rest.py b/samples/client/echo_api/python/openapi_client/rest.py
index b97741ddfce..d2bd065dc08 100644
--- a/samples/client/echo_api/python/openapi_client/rest.py
+++ b/samples/client/echo_api/python/openapi_client/rest.py
@@ -77,6 +77,7 @@ class RESTClientObject:
             "ca_certs": configuration.ssl_ca_cert,
             "cert_file": configuration.cert_file,
             "key_file": configuration.key_file,
+            "ca_cert_data": configuration.ca_cert_data,
         }
         if configuration.assert_hostname is not None:
             pool_args['assert_hostname'] = (
diff --git a/samples/openapi3/client/petstore/python-aiohttp/petstore_api/configuration.py b/samples/openapi3/client/petstore/python-aiohttp/petstore_api/configuration.py
index 0282a0aa460..5738e19cf7b 100644
--- a/samples/openapi3/client/petstore/python-aiohttp/petstore_api/configuration.py
+++ b/samples/openapi3/client/petstore/python-aiohttp/petstore_api/configuration.py
@@ -17,7 +17,7 @@ import http.client as httplib
 import logging
 from logging import FileHandler
 import sys
-from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict
+from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict, Union
 from typing_extensions import NotRequired, Self
 
 import urllib3
@@ -168,6 +168,8 @@ class Configuration:
     :param ssl_ca_cert: str - the path to a file of concatenated CA certificates
       in PEM format.
     :param retries: Number of retries for API requests.
+    :param ca_cert_data: verify the peer using concatenated CA certificate data
+      in PEM (str) or DER (bytes) format.
 
     :Example:
 
@@ -257,13 +259,14 @@ conf = petstore_api.Configuration(
         password: Optional[str]=None,
         access_token: Optional[str]=None,
         signing_info: Optional[HttpSigningConfiguration]=None,
-        server_index: Optional[int]=None, 
+        server_index: Optional[int]=None,
         server_variables: Optional[ServerVariablesT]=None,
         server_operation_index: Optional[Dict[int, int]]=None,
         server_operation_variables: Optional[Dict[int, ServerVariablesT]]=None,
         ignore_operation_servers: bool=False,
         ssl_ca_cert: Optional[str]=None,
         retries: Optional[int] = None,
+        ca_cert_data: Optional[Union[str, bytes]] = None,
         *,
         debug: Optional[bool] = None,
     ) -> None:
@@ -346,6 +349,10 @@ conf = petstore_api.Configuration(
         self.ssl_ca_cert = ssl_ca_cert
         """Set this to customize the certificate file to verify the peer.
         """
+        self.ca_cert_data = ca_cert_data
+        """Set this to verify the peer using PEM (str) or DER (bytes)
+           certificate data.
+        """
         self.cert_file = None
         """client certificate file
         """
diff --git a/samples/openapi3/client/petstore/python-aiohttp/petstore_api/rest.py b/samples/openapi3/client/petstore/python-aiohttp/petstore_api/rest.py
index ec1da5adf9e..5ee6cd4b2df 100644
--- a/samples/openapi3/client/petstore/python-aiohttp/petstore_api/rest.py
+++ b/samples/openapi3/client/petstore/python-aiohttp/petstore_api/rest.py
@@ -57,7 +57,8 @@ class RESTClientObject:
         self.maxsize = configuration.connection_pool_maxsize
 
         self.ssl_context = ssl.create_default_context(
-            cafile=configuration.ssl_ca_cert
+            cafile=configuration.ssl_ca_cert,
+            cadata=configuration.ca_cert_data,
         )
         if configuration.cert_file:
             self.ssl_context.load_cert_chain(
diff --git a/samples/openapi3/client/petstore/python/petstore_api/configuration.py b/samples/openapi3/client/petstore/python/petstore_api/configuration.py
index f374b0bc53d..cb081f807f5 100755
--- a/samples/openapi3/client/petstore/python/petstore_api/configuration.py
+++ b/samples/openapi3/client/petstore/python/petstore_api/configuration.py
@@ -18,7 +18,7 @@ import logging
 from logging import FileHandler
 import multiprocessing
 import sys
-from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict
+from typing import Any, ClassVar, Dict, List, Literal, Optional, TypedDict, Union
 from typing_extensions import NotRequired, Self
 
 import urllib3
@@ -169,6 +169,8 @@ class Configuration:
     :param ssl_ca_cert: str - the path to a file of concatenated CA certificates
       in PEM format.
     :param retries: Number of retries for API requests.
+    :param ca_cert_data: verify the peer using concatenated CA certificate data
+      in PEM (str) or DER (bytes) format.
 
     :Example:
 
@@ -258,13 +260,14 @@ conf = petstore_api.Configuration(
         password: Optional[str]=None,
         access_token: Optional[str]=None,
         signing_info: Optional[HttpSigningConfiguration]=None,
-        server_index: Optional[int]=None, 
+        server_index: Optional[int]=None,
         server_variables: Optional[ServerVariablesT]=None,
         server_operation_index: Optional[Dict[int, int]]=None,
         server_operation_variables: Optional[Dict[int, ServerVariablesT]]=None,
         ignore_operation_servers: bool=False,
         ssl_ca_cert: Optional[str]=None,
         retries: Optional[int] = None,
+        ca_cert_data: Optional[Union[str, bytes]] = None,
         *,
         debug: Optional[bool] = None,
     ) -> None:
@@ -347,6 +350,10 @@ conf = petstore_api.Configuration(
         self.ssl_ca_cert = ssl_ca_cert
         """Set this to customize the certificate file to verify the peer.
         """
+        self.ca_cert_data = ca_cert_data
+        """Set this to verify the peer using PEM (str) or DER (bytes)
+           certificate data.
+        """
         self.cert_file = None
         """client certificate file
         """
diff --git a/samples/openapi3/client/petstore/python/petstore_api/rest.py b/samples/openapi3/client/petstore/python/petstore_api/rest.py
index 3c7cc883f69..abc7aa28938 100755
--- a/samples/openapi3/client/petstore/python/petstore_api/rest.py
+++ b/samples/openapi3/client/petstore/python/petstore_api/rest.py
@@ -76,6 +76,7 @@ class RESTClientObject:
             "ca_certs": configuration.ssl_ca_cert,
             "cert_file": configuration.cert_file,
             "key_file": configuration.key_file,
+            "ca_cert_data": configuration.ca_cert_data,
         }
         if configuration.assert_hostname is not None:
             pool_args['assert_hostname'] = (