From 5278fbfcf7edd99606ac324a328a15d08e9684ed Mon Sep 17 00:00:00 2001
From: An Long <aisk1988@gmail.com>
Date: Sat, 29 Aug 2026 18:53:37 +0900
Subject: [PATCH] gh-156555: Fix crash in sqlite3.Row() with uninitialised
 Cursor

---
 Lib/test/test_sqlite3/test_factory.py                      | 6 ++++++
 .../Library/2026-08-29-18-52-43.gh-issue-156555.nNV61R.rst | 3 +++
 Modules/_sqlite/row.c                                      | 7 +++++++
 3 files changed, 16 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2026-08-29-18-52-43.gh-issue-156555.nNV61R.rst

diff --git a/Lib/test/test_sqlite3/test_factory.py b/Lib/test/test_sqlite3/test_factory.py
index 2dd42921d31ddd5..2679ff8ace58b6e 100644
--- a/Lib/test/test_sqlite3/test_factory.py
+++ b/Lib/test/test_sqlite3/test_factory.py
@@ -280,6 +280,12 @@ class FakeCursor(str):
         self.assertRaises(TypeError, self.con.cursor, FakeCursor)
         self.assertRaises(TypeError, sqlite.Row, FakeCursor(), ())
 
+    def test_uninitialised_cursor(self):
+        cur = sqlite.Cursor.__new__(sqlite.Cursor)
+        with self.assertRaisesRegex(sqlite.ProgrammingError,
+                                    "Base Cursor.__init__ not called"):
+            sqlite.Row(cur, ())
+
 
 class TextFactoryTests(MemoryDatabaseMixin, unittest.TestCase):
 
diff --git a/Misc/NEWS.d/next/Library/2026-08-29-18-52-43.gh-issue-156555.nNV61R.rst b/Misc/NEWS.d/next/Library/2026-08-29-18-52-43.gh-issue-156555.nNV61R.rst
new file mode 100644
index 000000000000000..8bbf2583338d7d7
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-08-29-18-52-43.gh-issue-156555.nNV61R.rst
@@ -0,0 +1,3 @@
+Fix a crash in :class:`sqlite3.Row` when it is given a
+:class:`sqlite3.Cursor` whose ``__init__()`` was not called; it now raises
+:exc:`sqlite3.ProgrammingError` instead.
diff --git a/Modules/_sqlite/row.c b/Modules/_sqlite/row.c
index 8646f591ef5169f..29967671eac3723 100644
--- a/Modules/_sqlite/row.c
+++ b/Modules/_sqlite/row.c
@@ -88,6 +88,13 @@ pysqlite_row_new_impl(PyTypeObject *type, pysqlite_Cursor *cursor,
 
     assert(type != NULL && type->tp_alloc != NULL);
 
+    if (!cursor->initialized) {
+        pysqlite_state *state = pysqlite_get_state_by_type(type);
+        PyErr_SetString(state->ProgrammingError,
+                        "Base Cursor.__init__ not called.");
+        return NULL;
+    }
+
     self = (pysqlite_Row *) type->tp_alloc(type, 0);
     if (self == NULL)
         return NULL;