fix(proxy): scope file list pagination cursors to the caller

GET /v1/files filters data down to the caller's own managed files but left first_id and last_id as the upstream page's, so a non-owner got back file ids belonging to other users even with an empty data array

enterprise/litellm_enterprise/proxy/hooks/managed_files.py

@@ -1270,10 +1270,25 @@ class _PROXY_LiteLLMManagedFiles(CustomLogger, BaseFileEndpoints):
                     )
                     ## Filter the response to only include the files created by the user
                     response.data = user_created_file_ids  # type: ignore
+                    self._scope_list_page_cursors(response, user_created_file_ids)
                     return response
             return response
         return response
 
+    @staticmethod
+    def _scope_list_page_cursors(response: AsyncCursorPage, data: List[OpenAIFileObject]) -> None:
+        """Rebuild ``first_id`` / ``last_id`` from the caller-scoped page.
+
+        The upstream cursors point at rows that were just filtered out, so
+        leaving them in place discloses other callers' file ids.
+        """
+        if hasattr(response, "first_id"):
+            response.first_id = data[0].id if data else None
+        if hasattr(response, "last_id"):
+            response.last_id = data[-1].id if data else None
+        if not data and hasattr(response, "has_more"):
+            response.has_more = False
+
     async def afile_retrieve(
         self, file_id: str, litellm_parent_otel_span: Optional[Span], llm_router=None
     ) -> OpenAIFileObject:

tests/enterprise/litellm_enterprise/proxy/hooks/test_managed_files.py

@@ -2861,3 +2861,103 @@ async def test_same_user_different_keys_can_access_batch():
     assert "batch_id" in result2
     # Both keys should get the same result
     assert result1["batch_id"] == result2["batch_id"]
+
+
+@pytest.mark.asyncio
+async def test_file_list_cursors_are_scoped_to_the_caller():
+    """A non-owner must not learn other callers' file ids through the page cursors."""
+    from openai.pagination import AsyncCursorPage
+    from openai.types import FileObject
+
+    from litellm.proxy._types import UserAPIKeyAuth
+
+    owner_file = FileObject(
+        id="file-owner-1",
+        bytes=100,
+        created_at=1,
+        filename="owner.jsonl",
+        object="file",
+        purpose="batch",
+        status="processed",
+    )
+    upstream_page = AsyncCursorPage[FileObject].construct(
+        data=[owner_file],
+        has_more=True,
+        first_id=owner_file.id,
+        last_id=owner_file.id,
+        object="list",
+    )
+
+    prisma_client = AsyncMock()
+    prisma_client.db.litellm_managedfiletable.find_many.return_value = []
+    proxy_managed_files = _PROXY_LiteLLMManagedFiles(
+        DualCache(), prisma_client=prisma_client
+    )
+
+    response = await proxy_managed_files.async_post_call_success_hook(
+        data={},
+        user_api_key_dict=UserAPIKeyAuth(
+            user_id="other-user", team_id="other-team", parent_otel_span=MagicMock()
+        ),
+        response=upstream_page,
+    )
+
+    assert response.data == []
+    assert response.first_id is None
+    assert response.last_id is None
+    assert response.has_more is False
+
+
+@pytest.mark.asyncio
+async def test_file_list_cursors_follow_the_owner_scoped_page():
+    from openai.pagination import AsyncCursorPage
+    from openai.types import FileObject
+
+    from litellm.proxy._types import UserAPIKeyAuth
+
+    def _raw_file(file_id: str) -> FileObject:
+        return FileObject(
+            id=file_id,
+            bytes=100,
+            created_at=1,
+            filename=f"{file_id}.jsonl",
+            object="file",
+            purpose="batch",
+            status="processed",
+        )
+
+    upstream_page = AsyncCursorPage[FileObject].construct(
+        data=[_raw_file("file-someone-else"), _raw_file("file-mine")],
+        has_more=False,
+        first_id="file-someone-else",
+        last_id="file-mine",
+        object="list",
+    )
+
+    managed_row = MagicMock()
+    managed_row.file_object = {
+        "id": "litellm_proxy:mine",
+        "bytes": 100,
+        "created_at": 1,
+        "filename": "mine.jsonl",
+        "object": "file",
+        "purpose": "batch",
+        "status": "processed",
+    }
+    prisma_client = AsyncMock()
+    prisma_client.db.litellm_managedfiletable.find_many.return_value = [managed_row]
+    proxy_managed_files = _PROXY_LiteLLMManagedFiles(
+        DualCache(), prisma_client=prisma_client
+    )
+
+    response = await proxy_managed_files.async_post_call_success_hook(
+        data={},
+        user_api_key_dict=UserAPIKeyAuth(
+            user_id="mine-user", parent_otel_span=MagicMock()
+        ),
+        response=upstream_page,
+    )
+
+    assert [file_object.id for file_object in response.data] == ["litellm_proxy:mine"]
+    assert response.first_id == "litellm_proxy:mine"
+    assert response.last_id == "litellm_proxy:mine"