diff --git a/docs/releases/4.5.0.rst b/docs/releases/4.5.0.rst
index 6b6201a90..2560d5a61 100644
--- a/docs/releases/4.5.0.rst
+++ b/docs/releases/4.5.0.rst
@@ -66,6 +66,8 @@ Other changes
   This makes it easier to delete objects created under a legacy IRRD that
   do not meet current validation requirements. Authentication requirements
   have not been changed.
+* Authoritative creation or updating of route(6) objects for 0.0.0.0/0,
+  0.0.0.0/32, ::/0 and ::/128 is no longer allowed.
 * The ``sources.{name}.nrtm_query_serial_days_limit`` setting was added to
   limit the age of the oldest serial that can be requested over NRTMv3.
 * The ``irrd_update_database`` command now starts counting serials from
diff --git a/irrd/updates/tests/test_validators.py b/irrd/updates/tests/test_validators.py
index 0626e1833..6d3b525af 100644
--- a/irrd/updates/tests/test_validators.py
+++ b/irrd/updates/tests/test_validators.py
@@ -851,6 +851,14 @@ def prepare_mocks(self, monkeypatch):
         validator = RulesValidator(mock_dh)
         yield validator, mock_dsq, mock_dh
 
+    def test_check_rejects_default_gateway_route(self, prepare_mocks):
+        validator, mock_dsq, mock_dh = prepare_mocks
+        route = rpsl_object_from_text(SAMPLE_ROUTE.replace("192.0.02.0/24", "0.0.0.0/0"))
+        invalid = validator.validate(route, UpdateRequestType.CREATE)
+        assert not invalid.is_valid()
+        assert set(invalid.error_messages) == {"Route(6) objects for 0.0.0.0/0 are not permitted."}
+        assert validator.validate(route, UpdateRequestType.DELETE).is_valid()
+
     def test_check_suspended_mntner_with_same_pk(self, prepare_mocks, monkeypatch):
         validator, mock_dsq, mock_dh = prepare_mocks
         monkeypatch.setattr(
diff --git a/irrd/updates/validators.py b/irrd/updates/validators.py
index d2b7e4a9d..dbbccfea2 100644
--- a/irrd/updates/validators.py
+++ b/irrd/updates/validators.py
@@ -13,6 +13,8 @@
 from irrd.rpsl.rpsl_objects import (
     PROTECTED_NAME_OBJECT_CLASSES,
     RPSLMntner,
+    RPSLRoute,
+    RPSLRoute6,
     RPSLSet,
     rpsl_object_from_text,
 )
@@ -694,15 +696,29 @@ class RulesValidator:
     This means: anything that is not authentication, references, RPKI or scope filter.
     """
 
+    BLOCKLIST_ROUTES = [
+        IP("0.0.0.0/0"),
+        IP("0.0.0.0/32"),
+        IP("::/0"),
+        IP("::/128"),
+    ]
+
     def __init__(self, database_handler: DatabaseHandler) -> None:
         self.database_handler = database_handler
 
     def validate(self, rpsl_obj: RPSLObject, request_type: UpdateRequestType) -> ValidatorResult:
         result = ValidatorResult()
 
+        if (
+            request_type != UpdateRequestType.DELETE
+            and (isinstance(rpsl_obj, RPSLRoute) or isinstance(rpsl_obj, RPSLRoute6))
+            and rpsl_obj.prefix in self.BLOCKLIST_ROUTES
+        ):
+            result.error_messages.add(f"Route(6) objects for {rpsl_obj.prefix} are not permitted.")
+
         if (
             request_type == UpdateRequestType.CREATE
-            and rpsl_obj.rpsl_object_class == "mntner"
+            and isinstance(rpsl_obj, RPSLMntner)
             and self._check_suspended_mntner_with_same_pk(rpsl_obj.pk(), rpsl_obj.source())
         ):
             result.error_messages.add(