diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1ba2701..41a73ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,11 @@
+# 6.3.3 (XXXX-XX-XX)
+
+# Changes
+
+- Ensure that curated path and incoming path definitions do not point
+  outside of the storage-root tree.
+
+
 # 6.3.2 (2026-07-07)
 
 ## Changes
diff --git a/dump_things_service/collection_endpoints.py b/dump_things_service/collection_endpoints.py
index aa302a9..6074895 100644
--- a/dump_things_service/collection_endpoints.py
+++ b/dump_things_service/collection_endpoints.py
@@ -136,6 +136,9 @@ async def create_or_replace_collection(
     # Check for incoming directory if any of the tokens allows writing
     validate_incoming_paths(abstract_config, body)
 
+    # Check for paths in the storage route
+    validate_path_destinations(instance_state, body)
+
     # If the configuration already exist, we have to delete it here and
     # manifest the reduced configuration. This ensures that the new collection
     # is fully manifested later
@@ -279,3 +282,33 @@ def validate_incoming_paths(
                     status_code=HTTP_406_NOT_ACCEPTABLE,
                     detail=detail,
                 )
+
+
+def validate_path_destinations(
+    instance_state: InstanceState,
+    collection_request: CollectionRequest,
+):
+    validate_path_destination(
+        instance_state=instance_state,
+        path=collection_request.curated,
+        name='curated',
+    )
+    if collection_request.incoming is not None:
+        validate_path_destination(
+            instance_state=instance_state,
+            path=collection_request.incoming,
+            name='incoming',
+        )
+
+
+def validate_path_destination(
+    instance_state: InstanceState,
+    path: PurePosixPath,
+    name: str,
+):
+    abs_path = (instance_state.store_path / Path(path)).resolve().absolute()
+    if not abs_path.is_relative_to(instance_state.store_path):
+        raise HTTPException(
+            status_code=HTTP_406_NOT_ACCEPTABLE,
+            detail=f"{name}-path '{path}' is outside of the store path.",
+        )
diff --git a/dump_things_service/tests/test_paths.py b/dump_things_service/tests/test_paths.py
new file mode 100644
index 0000000..aac8296
--- /dev/null
+++ b/dump_things_service/tests/test_paths.py
@@ -0,0 +1,55 @@
+from pathlib import (
+    Path,
+    PurePosixPath,
+)
+
+from dump_things_service import HTTP_406_NOT_ACCEPTABLE
+from dump_things_service.collection_endpoints import CollectionRequest
+
+# Path to a local simple test schema
+test_schema_location = str((Path(__file__).parent / 'testschema.yaml').absolute())
+
+test_curated_path_collection_name = 'test_curated_path_collection'
+test_curated_path_collection_request = CollectionRequest(
+    name=test_curated_path_collection_name,
+    default_token='test_default_token',
+    curated=PurePosixPath('..'),
+    schema=test_schema_location,
+)
+
+test_incoming_path_collection_name = 'test_incoming_path_collection'
+test_incoming_path_collection_request = CollectionRequest(
+    name=test_incoming_path_collection_name,
+    default_token='test_default_token',
+    curated=PurePosixPath('curated/'),
+    schema=test_schema_location,
+    incoming=PurePosixPath('..'),
+)
+
+
+def test_curated_path(fastapi_client_simple):
+    test_client, _, admin_token = fastapi_client_simple
+
+    # Try to add a collection with an illegal curated path
+    response = test_client.post(
+        '/collections',
+        headers={'x-dumpthings-token': admin_token},
+        json=test_curated_path_collection_request.model_dump(
+            mode='json', by_alias=True
+        ),
+    )
+    assert response.status_code == HTTP_406_NOT_ACCEPTABLE
+
+
+def test_incoming_path(fastapi_client_simple):
+    test_client, _, admin_token = fastapi_client_simple
+
+    # Try to add a collection with an illegal curated path
+    response = test_client.post(
+        '/collections',
+        headers={'x-dumpthings-token': admin_token},
+        json=test_incoming_path_collection_request.model_dump(
+            mode='json', by_alias=True
+        ),
+    )
+    assert response.status_code == HTTP_406_NOT_ACCEPTABLE