diff --git a/supabase/migrations/020_swarm_runner_registry.sql b/supabase/migrations/020_swarm_runner_registry.sql
index d23ba8a..f797f0c 100644
--- a/supabase/migrations/020_swarm_runner_registry.sql
+++ b/supabase/migrations/020_swarm_runner_registry.sql
@@ -189,6 +189,6 @@ $$;
 
 ALTER TABLE public.task_runners ENABLE ROW LEVEL SECURITY;
 
--- Admins can read runner status for observability
+-- Service role can read runner status; later migrations add super-admin observability.
 CREATE POLICY "task_runners_select" ON public.task_runners
-  FOR SELECT USING (true);
+  FOR SELECT TO service_role USING (true);
diff --git a/supabase/migrations/036_file_attachments.sql b/supabase/migrations/036_file_attachments.sql
index 319eb83..d113b30 100644
--- a/supabase/migrations/036_file_attachments.sql
+++ b/supabase/migrations/036_file_attachments.sql
@@ -58,11 +58,11 @@ CREATE POLICY "Users can delete own workspace attachments"
 
 -- Service role (task runner) can read/insert attachments
 CREATE POLICY "Service role can read attachments"
-    ON public.file_attachments FOR SELECT
+    ON public.file_attachments FOR SELECT TO service_role
     USING (true);
 
 CREATE POLICY "Service role can insert attachments"
-    ON public.file_attachments FOR INSERT
+    ON public.file_attachments FOR INSERT TO service_role
     WITH CHECK (true);
 
 -- ─── Storage bucket ─────────────────────────────────────────────────────────
diff --git a/supabase/migrations/040_team_memory_search.sql b/supabase/migrations/040_team_memory_search.sql
index ad10722..fa07623 100644
--- a/supabase/migrations/040_team_memory_search.sql
+++ b/supabase/migrations/040_team_memory_search.sql
@@ -60,4 +60,4 @@ CREATE POLICY "team_memory_delete" ON public.team_memory
 -- ────────────────────────────────────────────────────────────────────────────
 
 CREATE POLICY "team_memory_insert_service" ON public.team_memory
-  FOR INSERT WITH CHECK (true);
+  FOR INSERT TO service_role WITH CHECK (true);
diff --git a/supabase/migrations/062_knowledge_base.sql b/supabase/migrations/062_knowledge_base.sql
index 45c8af7..22a700b 100644
--- a/supabase/migrations/062_knowledge_base.sql
+++ b/supabase/migrations/062_knowledge_base.sql
@@ -121,7 +121,7 @@ CREATE POLICY "knowledge_chunks_select" ON public.knowledge_chunks
 
 -- Insert/delete by service role (processing pipeline) — service role bypasses RLS
 CREATE POLICY "knowledge_chunks_insert" ON public.knowledge_chunks
-  FOR INSERT WITH CHECK (true);
+  FOR INSERT TO service_role WITH CHECK (true);
 
 CREATE POLICY "knowledge_chunks_delete" ON public.knowledge_chunks
   FOR DELETE USING (public.is_workspace_member(workspace_id));
diff --git a/supabase/migrations/071_chat_widget.sql b/supabase/migrations/071_chat_widget.sql
index 0642f39..a009676 100644
--- a/supabase/migrations/071_chat_widget.sql
+++ b/supabase/migrations/071_chat_widget.sql
@@ -71,7 +71,7 @@ CREATE POLICY chat_sessions_workspace_read ON chat_sessions
 
 -- Service role bypass for task runner writes
 CREATE POLICY chat_sessions_service_write ON chat_sessions
-    FOR ALL
+    FOR ALL TO service_role
     USING (true)
     WITH CHECK (true);
 
diff --git a/supabase/migrations/078_google_connections.sql b/supabase/migrations/078_google_connections.sql
index 2c49ff8..fd9e059 100644
--- a/supabase/migrations/078_google_connections.sql
+++ b/supabase/migrations/078_google_connections.sql
@@ -40,7 +40,7 @@ CREATE POLICY "google_connections_workspace_access"
 
 -- Service role can read/write (for Edge Functions + task runner)
 CREATE POLICY "google_connections_service_role"
-    ON public.google_connections FOR ALL
+    ON public.google_connections FOR ALL TO service_role
     USING (true)
     WITH CHECK (true);
 
diff --git a/supabase/migrations/082_harden_service_role_rls_policies.sql b/supabase/migrations/082_harden_service_role_rls_policies.sql
new file mode 100644
index 0000000..70cc05a
--- /dev/null
+++ b/supabase/migrations/082_harden_service_role_rls_policies.sql
@@ -0,0 +1,60 @@
+-- SPDX-License-Identifier: AGPL-3.0-or-later
+-- Copyright (C) 2026 CrewForm
+--
+-- 082_harden_service_role_rls_policies.sql
+--
+-- Tighten policies that were intended for trusted backend/service-role writes.
+-- Without an explicit TO clause, PostgreSQL policies apply to PUBLIC, which can
+-- make Supabase anon/authenticated clients eligible for the policy.
+
+-- Chat widget sessions: workspace members keep the separate read policy;
+-- trusted backend writes are limited to service_role.
+DROP POLICY IF EXISTS chat_sessions_service_write ON public.chat_sessions;
+CREATE POLICY chat_sessions_service_write
+  ON public.chat_sessions
+  FOR ALL TO service_role
+  USING (true)
+  WITH CHECK (true);
+
+-- Google OAuth tokens: only service role should read/write token material.
+DROP POLICY IF EXISTS "google_connections_service_role" ON public.google_connections;
+CREATE POLICY "google_connections_service_role"
+  ON public.google_connections
+  FOR ALL TO service_role
+  USING (true)
+  WITH CHECK (true);
+
+-- File attachment metadata: workspace policies handle user access; service
+-- access is limited to the task runner/backend.
+DROP POLICY IF EXISTS "Service role can read attachments" ON public.file_attachments;
+CREATE POLICY "Service role can read attachments"
+  ON public.file_attachments
+  FOR SELECT TO service_role
+  USING (true);
+
+DROP POLICY IF EXISTS "Service role can insert attachments" ON public.file_attachments;
+CREATE POLICY "Service role can insert attachments"
+  ON public.file_attachments
+  FOR INSERT TO service_role
+  WITH CHECK (true);
+
+-- Team memory and knowledge chunks are inserted by backend pipelines.
+DROP POLICY IF EXISTS "team_memory_insert_service" ON public.team_memory;
+CREATE POLICY "team_memory_insert_service"
+  ON public.team_memory
+  FOR INSERT TO service_role
+  WITH CHECK (true);
+
+DROP POLICY IF EXISTS "knowledge_chunks_insert" ON public.knowledge_chunks;
+CREATE POLICY "knowledge_chunks_insert"
+  ON public.knowledge_chunks
+  FOR INSERT TO service_role
+  WITH CHECK (true);
+
+-- Runner status should not be public. Service-role task runner access bypasses
+-- RLS; super admins can still read status for observability.
+DROP POLICY IF EXISTS "task_runners_select" ON public.task_runners;
+CREATE POLICY "task_runners_select"
+  ON public.task_runners
+  FOR SELECT TO authenticated
+  USING (public.is_super_admin());