diff --git a/cvat/apps/analytics_report/permissions.py b/cvat/apps/analytics_report/permissions.py
index e6177b1d4df8..d93418398902 100644
--- a/cvat/apps/analytics_report/permissions.py
+++ b/cvat/apps/analytics_report/permissions.py
@@ -70,7 +70,7 @@ def get_scopes(request, view, obj):
             {
                 "list": Scopes.LIST,
                 "create": Scopes.CREATE,
-            }.get(view.action, None)
+            }[view.action]
         ]
 
     def get_resource(self):
diff --git a/cvat/apps/engine/permissions.py b/cvat/apps/engine/permissions.py
index 92d1b107b747..70c147a4661f 100644
--- a/cvat/apps/engine/permissions.py
+++ b/cvat/apps/engine/permissions.py
@@ -65,7 +65,7 @@ def get_scopes(request, view, obj):
             ('about', 'GET'): Scopes.VIEW,
             ('plugins', 'GET'): Scopes.VIEW,
             ('share', 'GET'): Scopes.LIST_CONTENT,
-        }.get((view.action, request.method))]
+        }[(view.action, request.method)]]
 
     def get_resource(self):
         return None
@@ -100,7 +100,7 @@ def get_scopes(request, view, obj):
             'retrieve': Scopes.VIEW,
             'partial_update': Scopes.UPDATE,
             'destroy': Scopes.DELETE,
-        }.get(view.action)]
+        }[view.action]]
 
     @classmethod
     def create_scope_view(cls, iam_context, user_id):
@@ -178,7 +178,7 @@ def get_scopes(request, view, obj):
             'preview': Scopes.VIEW,
             'status': Scopes.VIEW,
             'actions': Scopes.VIEW,
-        }.get(view.action)]
+        }[view.action]]
 
     def get_resource(self):
         data = None
@@ -281,7 +281,7 @@ def get_scopes(request, view, obj):
             ('append_backup_chunk', 'PATCH'): Scopes.IMPORT_BACKUP,
             ('append_backup_chunk', 'HEAD'): Scopes.IMPORT_BACKUP,
             ('preview', 'GET'): Scopes.VIEW,
-        }.get((view.action, request.method))
+        }[(view.action, request.method)]
 
         scopes = []
         if scope == Scopes.UPDATE:
@@ -498,7 +498,7 @@ def get_scopes(request, view, obj) -> List[Scopes]:
             ('export_backup', 'GET'): Scopes.EXPORT_BACKUP,
             ('export_backup_v2', 'POST'): Scopes.EXPORT_BACKUP,
             ('preview', 'GET'): Scopes.VIEW,
-        }.get((view.action, request.method))
+        }[(view.action, request.method)]
 
         scopes = []
         if scope == Scopes.CREATE:
@@ -542,13 +542,8 @@ def get_scopes(request, view, obj) -> List[Scopes]:
 
             scopes.append(scope)
 
-        elif scope is not None:
-            scopes.append(scope)
-
         else:
-            # TODO: think if we can protect from missing endpoints
-            # assert False, "Unknown scope"
-            pass
+            scopes.append(scope)
 
         return scopes
 
@@ -729,7 +724,7 @@ def get_scopes(request, view, obj):
             ('dataset_export', 'GET'): Scopes.EXPORT_DATASET,
             ('export_dataset_v2', 'POST'): Scopes.EXPORT_DATASET if is_dataset_export(request) else Scopes.EXPORT_ANNOTATIONS,
             ('preview', 'GET'): Scopes.VIEW,
-        }.get((view.action, request.method))
+        }[(view.action, request.method)]
 
         scopes = []
         if scope == Scopes.UPDATE:
@@ -849,7 +844,7 @@ def get_scopes(request, view, obj):
             'destroy': Scopes.DELETE,
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         data = None
@@ -941,7 +936,7 @@ def get_scopes(request, view, obj):
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
             'comments': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         data = None
@@ -1065,7 +1060,7 @@ def get_scopes(request, view, obj):
             'destroy': Scopes.DELETE,
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         data = None
@@ -1127,7 +1122,7 @@ def get_scopes(request, view, obj):
             'destroy': Scopes.DELETE,
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         data = {}
@@ -1205,7 +1200,7 @@ def get_scopes(request, view, obj):
             'create': Scopes.CREATE,
             'destroy': Scopes.DELETE,
             'retrieve': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
 
 class RequestPermission(OpenPolicyAgentPermission):
@@ -1237,7 +1232,7 @@ def get_scopes(request, view, obj) -> List[Scopes]:
             ('list', 'GET'): Scopes.LIST,
             ('retrieve', 'GET'): Scopes.VIEW,
             ('cancel', 'POST'): Scopes.CANCEL,
-        }.get((view.action, request.method))]
+        }[(view.action, request.method)]]
 
 
     def get_resource(self):
diff --git a/cvat/apps/events/permissions.py b/cvat/apps/events/permissions.py
index 6f8ef8c4735c..a1b049cbbd4b 100644
--- a/cvat/apps/events/permissions.py
+++ b/cvat/apps/events/permissions.py
@@ -50,7 +50,7 @@ def get_scopes(request, view, obj):
         return [{
             ('create', 'POST'): Scopes.SEND_EVENTS,
             ('list', 'GET'): Scopes.DUMP_EVENTS,
-        }.get((view.action, request.method))]
+        }[(view.action, request.method)]]
 
     def get_resource(self):
         return None
diff --git a/cvat/apps/lambda_manager/permissions.py b/cvat/apps/lambda_manager/permissions.py
index e1f78ce58c49..94800f0edd5d 100644
--- a/cvat/apps/lambda_manager/permissions.py
+++ b/cvat/apps/lambda_manager/permissions.py
@@ -49,7 +49,7 @@ def get_scopes(request, view, obj):
             ('lambda_request', 'list'): Scopes.LIST_OFFLINE,
             ('lambda_request', 'retrieve'): Scopes.CALL_OFFLINE,
             ('lambda_request', 'destroy'): Scopes.CALL_OFFLINE,
-        }.get((view.basename, view.action), None)]
+        }[(view.basename, view.action)]]
 
     def get_resource(self):
         return None
diff --git a/cvat/apps/log_viewer/permissions.py b/cvat/apps/log_viewer/permissions.py
index cc92dd92c2eb..2d9500a29ea2 100644
--- a/cvat/apps/log_viewer/permissions.py
+++ b/cvat/apps/log_viewer/permissions.py
@@ -30,7 +30,7 @@ def get_scopes(request, view, obj):
         Scopes = __class__.Scopes
         return [{
             'list': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         return {
diff --git a/cvat/apps/organizations/permissions.py b/cvat/apps/organizations/permissions.py
index e0c3aa0b44df..3ee36fba1481 100644
--- a/cvat/apps/organizations/permissions.py
+++ b/cvat/apps/organizations/permissions.py
@@ -42,7 +42,7 @@ def get_scopes(request, view, obj):
             'destroy': Scopes.DELETE,
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
-        }.get(view.action, None)]
+        }[view.action]]
 
     def get_resource(self):
         if self.obj:
@@ -109,7 +109,7 @@ def get_scopes(request, view, obj):
             'accept': Scopes.ACCEPT,
             'decline': Scopes.DECLINE,
             'resend': Scopes.RESEND,
-        }.get(view.action)]
+        }[view.action]]
 
     def get_resource(self):
         data = None
@@ -172,12 +172,12 @@ def get_scopes(request, view, obj):
             'partial_update': Scopes.UPDATE,
             'retrieve': Scopes.VIEW,
             'destroy': Scopes.DELETE,
-        }.get(view.action)
+        }[view.action]
 
         if scope == Scopes.UPDATE:
             if request.data.get('role') != cast(Membership, obj).role:
                 scopes.append(Scopes.UPDATE_ROLE)
-        elif scope:
+        else:
             scopes.append(scope)
 
         return scopes
diff --git a/cvat/apps/quality_control/permissions.py b/cvat/apps/quality_control/permissions.py
index 0396adb3c490..0060a4d10bbf 100644
--- a/cvat/apps/quality_control/permissions.py
+++ b/cvat/apps/quality_control/permissions.py
@@ -85,7 +85,7 @@ def get_scopes(request, view, obj):
                 "create": Scopes.CREATE,
                 "retrieve": Scopes.VIEW,
                 "data": Scopes.VIEW,
-            }.get(view.action, None)
+            }[view.action]
         ]
 
     def get_resource(self):
@@ -158,7 +158,7 @@ def get_scopes(request, view, obj):
         return [
             {
                 "list": Scopes.LIST,
-            }.get(view.action, None)
+            }[view.action]
         ]
 
     def get_resource(self):
@@ -225,7 +225,7 @@ def get_scopes(request, view, obj):
                 "list": Scopes.LIST,
                 "retrieve": Scopes.VIEW,
                 "partial_update": Scopes.UPDATE,
-            }.get(view.action, None)
+            }[view.action]
         ]
 
     def get_resource(self):
diff --git a/cvat/apps/webhooks/permissions.py b/cvat/apps/webhooks/permissions.py
index e350605116f3..e5d132c55de6 100644
--- a/cvat/apps/webhooks/permissions.py
+++ b/cvat/apps/webhooks/permissions.py
@@ -62,7 +62,7 @@ def get_scopes(request, view, obj):
             ('deliveries', 'GET'): Scopes.VIEW,
             ('retrieve_delivery', 'GET'): Scopes.VIEW,
             ('redelivery', 'POST'): Scopes.UPDATE,
-        }.get((view.action, request.method))
+        }[(view.action, request.method)]
 
         scopes = []
         if scope == Scopes.CREATE:
@@ -70,7 +70,7 @@ def get_scopes(request, view, obj):
             if webhook_type in [m.value for m in WebhookTypeChoice]:
                 scope = Scopes(str(scope) + f'@{webhook_type}')
             scopes.append(scope)
-        elif scope in [Scopes.UPDATE, Scopes.DELETE, Scopes.LIST, Scopes.VIEW]:
+        else:
             scopes.append(scope)
 
         return scopes
diff --git a/cvat/apps/webhooks/views.py b/cvat/apps/webhooks/views.py
index 31de7a85d6af..66529bc6a7bd 100644
--- a/cvat/apps/webhooks/views.py
+++ b/cvat/apps/webhooks/views.py
@@ -109,7 +109,9 @@ def perform_create(self, serializer):
         ],
         responses={"200": OpenApiResponse(EventsSerializer)},
     )
-    @action(detail=False, methods=["GET"], serializer_class=EventsSerializer)
+    @action(detail=False, methods=["GET"], serializer_class=EventsSerializer,
+        permission_classes=[],
+    )
     def events(self, request):
         webhook_type = request.query_params.get("type", "all")
         events = None