From bfe8213b78ea3bda3b942d6474112e13edbde273 Mon Sep 17 00:00:00 2001
From: shamoon <4887959+shamoon@users.noreply.github.com>
Date: Tue, 1 Sep 2026 07:45:47 -0700
Subject: [PATCH] Fix: re-use permitted_object_ids

---
 src/documents/serialisers.py              |  3 +++
 src/documents/tests/test_tag_hierarchy.py | 31 +++++++++++++++++++++++
 src/documents/views.py                    |  4 ++-
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/src/documents/serialisers.py b/src/documents/serialisers.py
index dcb84b527..4193bed72 100644
--- a/src/documents/serialisers.py
+++ b/src/documents/serialisers.py
@@ -81,6 +81,7 @@ from documents.permissions import get_document_count_filter_for_user
 from documents.permissions import get_groups_with_only_permission
 from documents.permissions import has_perms_owner_aware
 from documents.permissions import permitted_document_ids
+from documents.permissions import restrict_queryset_to_visible
 from documents.permissions import set_permissions_for_object
 from documents.regex import validate_regex_pattern
 from documents.templating.filepath import validate_filepath_template_and_render
@@ -661,6 +662,8 @@ class TagSerializer(MatchingModelSerializer, OwnedObjectSerializer):
                 .select_related("owner")
                 .annotate(document_count=Count("documents", filter=filter_q))
             )
+            user = getattr(request, "user", None) if request else self.user
+            children = restrict_queryset_to_visible(children, user, "view_tag")
 
             view = self.context.get("view")
             ordering = (
diff --git a/src/documents/tests/test_tag_hierarchy.py b/src/documents/tests/test_tag_hierarchy.py
index 0bb4c75c5..c50812edc 100644
--- a/src/documents/tests/test_tag_hierarchy.py
+++ b/src/documents/tests/test_tag_hierarchy.py
@@ -1,5 +1,6 @@
 from unittest import mock
 
+from django.contrib.auth.models import Permission
 from django.contrib.auth.models import User
 from rest_framework.test import APITestCase
 
@@ -14,6 +15,36 @@ from documents.signals.handlers import run_workflows
 from documents.tests.utils import DirectoriesMixin
 
 
+class TestTagHierarchyPermissions(APITestCase):
+    def test_children_only_include_visible_tags(self) -> None:
+        owner = User.objects.create_user(username="owner")
+        requester = User.objects.create_user(username="requester")
+        requester.user_permissions.add(
+            Permission.objects.get(codename="view_tag"),
+        )
+        parent = Tag.objects.create(name="Visible parent", owner=requester)
+        hidden_child = Tag.objects.create(
+            name="Hidden child",
+            owner=owner,
+            tn_parent=parent,
+        )
+        self.client.force_authenticate(user=requester)
+
+        response = self.client.get("/api/tags/")
+
+        assert response.status_code == 200
+        parent_result = next(
+            tag for tag in response.data["results"] if tag["id"] == parent.pk
+        )
+        assert parent_result["children"] == []
+        assert hidden_child.pk not in response.data.get("all", [])
+
+        response = self.client.get(f"/api/tags/{parent.pk}/")
+
+        assert response.status_code == 200
+        assert response.data["children"] == []
+
+
 class TestTagHierarchy(DirectoriesMixin, APITestCase):
     def setUp(self) -> None:
         super().setUp()
diff --git a/src/documents/views.py b/src/documents/views.py
index c6f0aeb15..4bca07f20 100644
--- a/src/documents/views.py
+++ b/src/documents/views.py
@@ -635,7 +635,9 @@ class TagViewSet(PermissionsAwareDocumentCountMixin, ModelViewSet[Tag]):
                 annotate_document_count_for_related_queryset(
                     Tag.objects.filter(
                         pk__in=descendant_pks | {t.pk for t in all_tags},
-                    ).select_related("owner"),
+                    )
+                    .filter(pk__in=permitted_object_ids(user, Tag, "view_tag"))
+                    .select_related("owner"),
                     through_model=self.document_count_through,
                     related_object_field=self._get_document_count_source_field(),
                     user=user,