diff --git a/backend/app/feature_guards.py b/backend/app/feature_guards.py
index c4d3847..c1ea94f 100644
--- a/backend/app/feature_guards.py
+++ b/backend/app/feature_guards.py
@@ -55,9 +55,15 @@ async def require_portal_access(request: Request, user: dict = Depends(get_curre
         check(user, "requests" if item.get("kind") == "request" else "issues")
     elif path.endswith("/items") and request.method == "POST":
         payload = await request.json()
-        check(user, "new_requests" if isinstance(payload, dict) and payload.get("kind", "request") == "request" else "issues")
+        kind = str(payload.get("kind") or "").strip().lower() if isinstance(payload, dict) else ""
+        check(user, "new_requests" if not kind or kind == "request" else "issues")
     elif path.endswith(("/items", "/overview")) and request.query_params.get("kind"):
-        check(user, "requests" if request.query_params["kind"] == "request" else "issues")
+        kind = request.query_params["kind"].strip().lower()
+        if not kind:
+            check(user, "requests")
+            check(user, "issues")
+        else:
+            check(user, "requests" if kind == "request" else "issues")
     else:
         # Unfiltered lists/overview can include both kinds.
         check(user, "requests")
diff --git a/backend/tests/test_feature_access.py b/backend/tests/test_feature_access.py
index 6d52829..3dfd1b5 100644
--- a/backend/tests/test_feature_access.py
+++ b/backend/tests/test_feature_access.py
@@ -108,3 +108,13 @@ class FeatureAccessTests(TempDatabaseMixin, unittest.TestCase):
             with self.assertRaises(StopAsyncIteration):
                 await anext(iterator)
         asyncio.run(scenario())
+
+    def test_legacy_portal_kind_normalization_cannot_bypass_permissions(self):
+        update_permissions({'requests': False, 'new_requests': False, 'issues': True}, self.user['username'])
+        for kind in ['request', 'REQUEST', ' Request ', ' ', '']:
+            with self.subTest(kind=kind):
+                self.assertEqual(self.client.get('/portal/items', params={'kind': kind}).status_code, 403)
+                self.assertEqual(self.client.get('/portal/overview', params={'kind': kind}).status_code, 403)
+                self.assertEqual(self.client.post('/portal/items', json={'kind': kind}).status_code, 403)
+        self.assertEqual(self.client.post('/portal/items', json={'kind': None}).status_code, 403)
+        self.assertEqual(self.client.post('/portal/items', json={}).status_code, 403)