diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ec23c0bc..9c78e4042 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@
 - Add support for `data_view_id` in the `elasticstack_kibana_slo` resource ([#1305](https://github.com/elastic/terraform-provider-elasticstack/pull/1305))
 - Add support for `unenrollment_timeout` in `elasticstack_fleet_agent_policy` ([#1169](https://github.com/elastic/terraform-provider-elasticstack/issues/1169))
 - Handle default value for `allow_restricted_indices` in `elasticstack_elasticsearch_security_api_key` ([#1315](https://github.com/elastic/terraform-provider-elasticstack/pull/1315))
+- Fixed `nil` reference in kibana synthetics API client in case of response errors ([#1320](https://github.com/elastic/terraform-provider-elasticstack/pull/1320))
 
 ## [0.11.17] - 2025-07-21
 
diff --git a/libs/go-kibana-rest/docker-compose.yml b/libs/go-kibana-rest/docker-compose.yml
index 9374bdd1c..515a53e3c 100644
--- a/libs/go-kibana-rest/docker-compose.yml
+++ b/libs/go-kibana-rest/docker-compose.yml
@@ -1,6 +1,6 @@
 services:
   elasticsearch:
-    image: docker.elastic.co/elasticsearch/elasticsearch:9.1.3@sha256:d620e80b7222e32eff42ac0fc614a0a5753f6ce9859df33b9ddea49c3bf5fb01
+    image: docker.elastic.co/elasticsearch/elasticsearch:9.1.2@sha256:d1a8016cf55be8ffec635ed69f5a9acb0c459db35b46a4549ec5b2847a2f170a
     environment:
       cluster.name: test
       discovery.type: single-node
@@ -11,7 +11,7 @@ services:
     ports:
       - "9200:9200/tcp"
   set-kibana-password:
-    image: docker.elastic.co/kibana/kibana:9.1.3@sha256:26792c8e4a68ba0bff3efcc46755f60bf36bb16b2431014c210f2546ca1819ad
+    image: docker.elastic.co/kibana/kibana:9.0.3@sha256:c4c00a485fbc3619d8373f3bc74e9dd5b5a34380ef50442be4366e8fb57cd50a
     restart: on-failure
     links:
       - elasticsearch
@@ -22,7 +22,7 @@ services:
       elasticsearch:
         condition: service_started
   kibana:
-    image: docker.elastic.co/kibana/kibana:9.1.3@sha256:26792c8e4a68ba0bff3efcc46755f60bf36bb16b2431014c210f2546ca1819ad
+    image: docker.elastic.co/kibana/kibana:9.0.3@sha256:c4c00a485fbc3619d8373f3bc74e9dd5b5a34380ef50442be4366e8fb57cd50a
     environment:
       SERVER_NAME: kibana
       ELASTICSEARCH_HOSTS: http://es:9200
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_logstash_pipeline.go b/libs/go-kibana-rest/kbapi/api.kibana_logstash_pipeline.go
index 698e399b0..458924b24 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_logstash_pipeline.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_logstash_pipeline.go
@@ -73,7 +73,7 @@ func newKibanaLogstashPipelineGetFunc(c *resty.Client) KibanaLogstashPipelineGet
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		logstashPipeline := &LogstashPipeline{}
 		err = json.Unmarshal(resp.Body(), logstashPipeline)
@@ -97,7 +97,7 @@ func newKibanaLogstashPipelineListFunc(c *resty.Client) KibanaLogstashPipelineLi
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		logstashPipelinesList := &LogstashPipelinesList{}
 		err = json.Unmarshal(resp.Body(), logstashPipelinesList)
@@ -140,7 +140,7 @@ func newKibanaLogstashPipelineCreateOrUpdateFunc(c *resty.Client) KibanaLogstash
 
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		// Retrive the object to return it
@@ -174,7 +174,7 @@ func newKibanaLogstashPipelineDeleteFunc(c *resty.Client) KibanaLogstashPipeline
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return NewAPIError(resp.StatusCode(), resp.Status())
+			return NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		return nil
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_role_management.go b/libs/go-kibana-rest/kbapi/api.kibana_role_management.go
index b3a557c1f..faaa2762a 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_role_management.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_role_management.go
@@ -100,7 +100,7 @@ func newKibanaRoleManagementGetFunc(c *resty.Client) KibanaRoleManagementGet {
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaRole := &KibanaRole{}
 		err = json.Unmarshal(resp.Body(), kibanaRole)
@@ -124,7 +124,7 @@ func newKibanaRoleManagementListFunc(c *resty.Client) KibanaRoleManagementList {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaRoles := make(KibanaRoles, 0, 1)
 		err = json.Unmarshal(resp.Body(), &kibanaRoles)
@@ -165,7 +165,7 @@ func newKibanaRoleManagementCreateOrUpdateFunc(c *resty.Client) KibanaRoleManage
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		// Retrive the object to return it
@@ -197,7 +197,7 @@ func newKibanaRoleManagementDeleteFunc(c *resty.Client) KibanaRoleManagementDele
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return NewAPIError(resp.StatusCode(), resp.Status())
+			return NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		return nil
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_save_object.go b/libs/go-kibana-rest/kbapi/api.kibana_save_object.go
index a04f18145..03423a42c 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_save_object.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_save_object.go
@@ -85,7 +85,7 @@ func newKibanaSavedObjectGetFunc(c *resty.Client) KibanaSavedObjectGet {
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 
 		}
 		var data map[string]interface{}
@@ -165,7 +165,7 @@ func newKibanaSavedObjectFindFunc(c *resty.Client) KibanaSavedObjectFind {
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 
 		}
 		var data map[string]interface{}
@@ -214,7 +214,7 @@ func newKibanaSavedObjectCreateFunc(c *resty.Client) KibanaSavedObjectCreate {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		var dataResponse map[string]interface{}
 		err = json.Unmarshal(resp.Body(), &dataResponse)
@@ -263,7 +263,7 @@ func newKibanaSavedObjectUpdateFunc(c *resty.Client) KibanaSavedObjectUpdate {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		var dataResponse map[string]interface{}
 		err = json.Unmarshal(resp.Body(), &dataResponse)
@@ -304,7 +304,7 @@ func newKibanaSavedObjectDeleteFunc(c *resty.Client) KibanaSavedObjectDelete {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return NewAPIError(resp.StatusCode(), resp.Status())
+			return NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		var dataResponse map[string]interface{}
 		err = json.Unmarshal(resp.Body(), &dataResponse)
@@ -356,7 +356,7 @@ func newKibanaSavedObjectExportFunc(c *resty.Client) KibanaSavedObjectExport {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		data := resp.Body()
@@ -396,7 +396,7 @@ func newKibanaSavedObjectImportFunc(c *resty.Client) KibanaSavedObjectImport {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		var dataResponse map[string]interface{}
 		err = json.Unmarshal(resp.Body(), &dataResponse)
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_shorten_url.go b/libs/go-kibana-rest/kbapi/api.kibana_shorten_url.go
index 257d9bb44..07c0a35f9 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_shorten_url.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_shorten_url.go
@@ -63,7 +63,7 @@ func newKibanaShortenURLCreateFunc(c *resty.Client) KibanaShortenURLCreate {
 
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 
 		shortenURLResponse := &ShortenURLResponse{}
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_spaces.go b/libs/go-kibana-rest/kbapi/api.kibana_spaces.go
index 9b1e7a9c7..0b49dfcde 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_spaces.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_spaces.go
@@ -87,7 +87,7 @@ func newKibanaSpaceGetFunc(c *resty.Client) KibanaSpaceGet {
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 
 		}
 		kibanaSpace := &KibanaSpace{}
@@ -113,7 +113,7 @@ func newKibanaSpaceListFunc(c *resty.Client) KibanaSpaceList {
 		}
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaSpaces := make(KibanaSpaces, 0, 1)
 		err = json.Unmarshal(resp.Body(), &kibanaSpaces)
@@ -148,7 +148,7 @@ func newKibanaSpaceCreateFunc(c *resty.Client) KibanaSpaceCreate {
 
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaSpace = &KibanaSpace{}
 		err = json.Unmarshal(resp.Body(), kibanaSpace)
@@ -189,7 +189,7 @@ func newKibanaSpaceCopySavedObjectsFunc(c *resty.Client) KibanaSpaceCopySavedObj
 
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return NewAPIError(resp.StatusCode(), resp.Status())
+			return NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		data := make(map[string]interface{})
 		err = json.Unmarshal(resp.Body(), &data)
@@ -205,7 +205,7 @@ func newKibanaSpaceCopySavedObjectsFunc(c *resty.Client) KibanaSpaceCopySavedObj
 			}
 		}
 		if len(errors) > 0 {
-			return NewAPIError(500, strings.Join(errors, "\n"))
+			return NewAPIError(500, "%s", strings.Join(errors, "\n"))
 		}
 
 		return nil
@@ -231,7 +231,7 @@ func newKibanaSpaceDeleteFunc(c *resty.Client) KibanaSpaceDelete {
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
 
-			return NewAPIError(resp.StatusCode(), resp.Status())
+			return NewAPIError(resp.StatusCode(), "%s", resp.Status())
 
 		}
 
@@ -261,7 +261,7 @@ func newKibanaSpaceUpdateFunc(c *resty.Client) KibanaSpaceUpdate {
 
 		log.Debug("Response: ", resp)
 		if resp.StatusCode() >= 300 {
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaSpace = &KibanaSpace{}
 		err = json.Unmarshal(resp.Body(), kibanaSpace)
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_status.go b/libs/go-kibana-rest/kbapi/api.kibana_status.go
index c6ad95539..6aec6a86e 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_status.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_status.go
@@ -29,7 +29,7 @@ func newKibanaStatusGetFunc(c *resty.Client) KibanaStatusGet {
 			if resp.StatusCode() == 404 {
 				return nil, nil
 			}
-			return nil, NewAPIError(resp.StatusCode(), resp.Status())
+			return nil, NewAPIError(resp.StatusCode(), "%s", resp.Status())
 		}
 		kibanaStatus := make(KibanaStatus)
 		err = json.Unmarshal(resp.Body(), &kibanaStatus)
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_synthetics.go b/libs/go-kibana-rest/kbapi/api.kibana_synthetics.go
index 6389d699f..283c27613 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_synthetics.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_synthetics.go
@@ -415,6 +415,9 @@ func newKibanaSyntheticsMonitorDeleteFunc(c *resty.Client) KibanaSyntheticsMonit
 		}
 
 		result, err := unmarshal(resp, []MonitorDeleteStatus{})
+		if err != nil {
+			return nil, err
+		}
 		return *result, err
 	}
 }
@@ -481,6 +484,9 @@ func newKibanaSyntheticsParameterDeleteFunc(c *resty.Client) KibanaSyntheticsPar
 		}
 
 		result, err := unmarshal(resp, []ParameterDeleteStatus{})
+		if err != nil {
+			return nil, err
+		}
 		return *result, err
 	}
 }
@@ -503,9 +509,9 @@ func handleKibanaError(err error, resp *resty.Response) error {
 		kibanaErr := KibanaError{}
 		err := json.Unmarshal(resp.Body(), &kibanaErr)
 		if err != nil {
-			return NewAPIError(resp.StatusCode(), resp.Status(), err)
+			return NewAPIError(resp.StatusCode(), "status: %s, err: %s", resp.Status(), err)
 		}
-		return NewAPIError(resp.StatusCode(), kibanaErr.Message, kibanaErr.Error)
+		return NewAPIError(resp.StatusCode(), "message: %s, err: %s", kibanaErr.Message, kibanaErr.Error)
 	}
 	return nil
 }
diff --git a/libs/go-kibana-rest/kbapi/api.kibana_synthetics_test.go b/libs/go-kibana-rest/kbapi/api.kibana_synthetics_test.go
index 1c48454a6..84f121e57 100644
--- a/libs/go-kibana-rest/kbapi/api.kibana_synthetics_test.go
+++ b/libs/go-kibana-rest/kbapi/api.kibana_synthetics_test.go
@@ -444,6 +444,7 @@ func (s *KBAPITestSuite) TestKibanaSyntheticsPrivateLocationAPI() {
 				created, err := pAPI.Create(ctx, cfg)
 
 				assert.NoError(s.T(), err)
+				assert.NotNil(s.T(), created)
 				assert.Equal(s.T(), created.Label, cfg.Label)
 				assert.Equal(s.T(), created.AgentPolicyId, cfg.AgentPolicyId)