diff --git a/prowler/CHANGELOG.md b/prowler/CHANGELOG.md
index d141e66e18..f89dfe39b5 100644
--- a/prowler/CHANGELOG.md
+++ b/prowler/CHANGELOG.md
@@ -20,6 +20,7 @@ All notable changes to the **Prowler SDK** are documented in this file.
 ### Fixed
 - Renamed `AdditionalUrls` to `AdditionalURLs` field in CheckMetadata [(#8639)](https://github.com/prowler-cloud/prowler/pull/8639)
 - TypeError from Python 3.9 in Security Hub module by updating type annotations [(#8619)](https://github.com/prowler-cloud/prowler/pull/8619)
+- KeyError when SecurityGroups field is missing in MemoryDB check [(#8666)](https://github.com/prowler-cloud/prowler/pull/8666)
 
 ---
 
diff --git a/prowler/providers/aws/services/memorydb/memorydb_service.py b/prowler/providers/aws/services/memorydb/memorydb_service.py
index 6bfbb255e3..e1a13fcba9 100644
--- a/prowler/providers/aws/services/memorydb/memorydb_service.py
+++ b/prowler/providers/aws/services/memorydb/memorydb_service.py
@@ -36,7 +36,7 @@ class MemoryDB(AWSService):
                                 region=regional_client.region,
                                 security_groups=[
                                     sg["SecurityGroupId"]
-                                    for sg in cluster["SecurityGroups"]
+                                    for sg in cluster.get("SecurityGroups", [])
                                     if sg["Status"] == "active"
                                 ],
                                 tls_enabled=cluster["TLSEnabled"],
diff --git a/tests/providers/aws/services/memorydb/memorydb_service_test.py b/tests/providers/aws/services/memorydb/memorydb_service_test.py
index 9b804449e9..8115317920 100644
--- a/tests/providers/aws/services/memorydb/memorydb_service_test.py
+++ b/tests/providers/aws/services/memorydb/memorydb_service_test.py
@@ -108,3 +108,61 @@ class Test_MemoryDB_Service:
                 snapshot_limit=5,
             )
         }
+
+
+def mock_make_api_call_no_security_groups(self, operation_name, kwargs):
+    """Mock that simulates a cluster response WITHOUT the SecurityGroups field"""
+    if operation_name == "DescribeClusters":
+        return {
+            "Clusters": [
+                {
+                    "Name": MEM_DB_CLUSTER_NAME,
+                    "Description": "Test cluster without SecurityGroups",
+                    "Status": "available",
+                    "NumberOfShards": 1,
+                    "AvailabilityMode": "singleaz",
+                    "Engine": "valkey",
+                    "EngineVersion": MEM_DB_ENGINE_VERSION,
+                    "EnginePatchVersion": "5.0.6",
+                    # SecurityGroups field is MISSING
+                    "TLSEnabled": True,
+                    "ARN": MEM_DB_CLUSTER_ARN,
+                    "SnapshotRetentionLimit": 5,
+                    "AutoMinorVersionUpgrade": True,
+                },
+            ]
+        }
+    return make_api_call(self, operation_name, kwargs)
+
+
+@patch(
+    "prowler.providers.aws.aws_provider.AwsProvider.generate_regional_clients",
+    new=mock_generate_regional_clients,
+)
+@patch(
+    "botocore.client.BaseClient._make_api_call",
+    new=mock_make_api_call_no_security_groups,
+)
+class Test_MemoryDB_Service_No_Security_Groups:
+    """Test class for clusters without SecurityGroups field"""
+
+    def test_describe_clusters_no_security_groups(self):
+        """Test that clusters without SecurityGroups field are handled correctly"""
+        aws_provider = set_mocked_aws_provider()
+        memorydb = MemoryDB(aws_provider)
+        assert memorydb.clusters == {
+            MEM_DB_CLUSTER_ARN: Cluster(
+                name=MEM_DB_CLUSTER_NAME,
+                arn=MEM_DB_CLUSTER_ARN,
+                number_of_shards=1,
+                engine="valkey",
+                engine_version=MEM_DB_ENGINE_VERSION,
+                engine_patch_version="5.0.6",
+                multi_az="singleaz",
+                region=AWS_REGION_US_EAST_1,
+                security_groups=[],
+                tls_enabled=True,
+                auto_minor_version_upgrade=True,
+                snapshot_limit=5,
+            )
+        }