diff --git a/api/src/api/v1/websocket.py b/api/src/api/v1/websocket.py
index 360f9d5..cc81078 100644
--- a/api/src/api/v1/websocket.py
+++ b/api/src/api/v1/websocket.py
@@ -538,6 +538,9 @@ class FormEventProcess:
             "value": any,
         }
         """
+        client_formula = event_data.get("formula")
+        # Формула клиента не должна уйти в рассылку, даже если запись не состоится.
+        _apply_saved_formula(event_data, None)
         if not await self._check_form_access(form_id=form_id, user=user):
             return None
 
@@ -549,7 +552,7 @@ class FormEventProcess:
             line_id=event_data["line_id"],
             column=event_data["column"],
             value=event_data["value"],
-            formula=event_data.get("formula"),
+            formula=client_formula,
             user=user,
         )
         _apply_saved_formula(event_data, formula)
@@ -774,6 +777,9 @@ class ProjectEventProcess:
             "value": any,
         }
         """
+        client_formula = event_data.get("formula")
+        # Формула клиента не должна уйти в рассылку, даже если запись не состоится.
+        _apply_saved_formula(event_data, None)
         project = await self.project_service.get(project_id=project_id, user=user)
         if not project:
             return None
@@ -785,7 +791,7 @@ class ProjectEventProcess:
             line_id=event_data["line_id"],
             column=event_data["column"],
             value=event_data["value"],
-            formula=event_data.get("formula"),
+            formula=client_formula,
             user=user,
         )
         _apply_saved_formula(event_data, formula)
diff --git a/api/tests/integration/test_cell_formula_ws_integration.py b/api/tests/integration/test_cell_formula_ws_integration.py
index 06a3120..54a08ea 100644
--- a/api/tests/integration/test_cell_formula_ws_integration.py
+++ b/api/tests/integration/test_cell_formula_ws_integration.py
@@ -188,3 +188,28 @@ def test_ws_project_report_cell_updated_carries_saved_formula(client, admin_toke
                 "DELETE FROM v3.rf_project_report_quarter WHERE rf_project_report_line_id = :l",
                 commit=True, l=line_id)
             _db_scalar("DELETE FROM v3.rf_project_report_line WHERE id = :l", commit=True, l=line_id)
+
+
+def test_ws_no_access_user_forged_formula_is_not_echoed(client, isp_tokens):
+    """I-1: пользователь без доступа к форме 1 (isp1) шлёт cell_updated с подделанной формулой:
+    в ответе/рассылке formula и formula_meta обнулены, строки cell_formula не появляется."""
+    count_sql = (
+        "SELECT count(*) FROM v3.cell_formula WHERE budget_form_id = 1 "
+        "AND line_id = 1 AND column_key = 'plan.q1'"
+    )
+    before = _db_scalar(count_sql)
+    prior = _db_scalar(PLAN_Q1_SQL)
+    try:
+        with client.websocket_connect(WS_URL) as ws:
+            ws.send_json({"event": "user_login", "data": {"token": isp_tokens["access_token"]}})
+            forged_meta = {"updated_by": {"id": 1, "full_name": "Forged"}, "updated_at": "2020-01-01T00:00:00"}
+            updated = _edit(ws, {"value": 777, "formula": "7*111", "formula_meta": forged_meta})
+        assert not updated.get("error"), updated
+        data = updated.get("data", {})
+        assert data.get("formula") is None, updated
+        assert data.get("formula_meta") is None, updated
+        assert _db_scalar(count_sql) == before
+        assert _db_scalar(PLAN_Q1_SQL) == prior
+    finally:
+        _cleanup_formula()
+        _restore_cell(prior)