[3.2.x] Fixed CVE-2022-34265 -- Protected Trunc(kind)/Extract(lookup_name) against SQL injection.

felixxm · felixxm · commit a9010fe5555e · 2022-07-04T08:41:33.000+02:00
Thanks Takuto Yoshikai (Aeye Security Lab) for the report.
diff --git a/django/db/backends/base/operations.py b/django/db/backends/base/operations.py
@@ -9,6 +9,7 @@
 from django.db.backends import utils
 from django.utils import timezone
 from django.utils.encoding import force_str
+from django.utils.regex_helper import _lazy_re_compile
 
 
 class BaseDatabaseOperations:
@@ -53,6 +54,8 @@ class BaseDatabaseOperations:
     # Prefix for EXPLAIN queries, or None EXPLAIN isn't supported.
     explain_prefix = None
 
+    extract_trunc_lookup_pattern = _lazy_re_compile(r"[\w\-_()]+")
+
     def __init__(self, connection):
         self.connection = connection
         self._cache = None
diff --git a/django/db/models/functions/datetime.py b/django/db/models/functions/datetime.py
@@ -41,6 +41,8 @@ def __init__(self, expression, lookup_name=None, tzinfo=None, **extra):
         super().__init__(expression, **extra)
 
     def as_sql(self, compiler, connection):
+        if not connection.ops.extract_trunc_lookup_pattern.fullmatch(self.lookup_name):
+            raise ValueError("Invalid lookup_name: %s" % self.lookup_name)
         sql, params = compiler.compile(self.lhs)
         lhs_output_field = self.lhs.output_field
         if isinstance(lhs_output_field, DateTimeField):
@@ -192,6 +194,8 @@ def __init__(self, expression, output_field=None, tzinfo=None, is_dst=None, **ex
         super().__init__(expression, output_field=output_field, **extra)
 
     def as_sql(self, compiler, connection):
+        if not connection.ops.extract_trunc_lookup_pattern.fullmatch(self.kind):
+            raise ValueError("Invalid kind: %s" % self.kind)
         inner_sql, inner_params = compiler.compile(self.lhs)
         tzname = None
         if isinstance(self.lhs.output_field, DateTimeField):
diff --git a/docs/releases/3.2.14.txt b/docs/releases/3.2.14.txt
@@ -5,3 +5,14 @@ Django 3.2.14 release notes
 *July 4, 2022*
 
 Django 3.2.14 fixes a security issue with severity "high" in 3.2.13.
+
+CVE-2022-34265: Potential SQL injection via ``Trunc(kind)`` and ``Extract(lookup_name)`` arguments
+==================================================================================================
+
+:class:`Trunc() <django.db.models.functions.Trunc>` and
+:class:`Extract() <django.db.models.functions.Extract>` database functions were
+subject to SQL injection if untrusted data was used as a
+``kind``/``lookup_name`` value.
+
+Applications that constrain the lookup name and kind choice to a known safe
+list are unaffected.
diff --git a/tests/db_functions/datetime/test_extract_trunc.py b/tests/db_functions/datetime/test_extract_trunc.py
@@ -177,6 +177,23 @@ def test_extract_year_lessthan_lookup(self):
                 self.assertEqual(qs.count(), 1)
                 self.assertGreaterEqual(str(qs.query).lower().count('extract'), 2)
 
+    def test_extract_lookup_name_sql_injection(self):
+        start_datetime = datetime(2015, 6, 15, 14, 30, 50, 321)
+        end_datetime = datetime(2016, 6, 15, 14, 10, 50, 123)
+        if settings.USE_TZ:
+            start_datetime = timezone.make_aware(start_datetime)
+            end_datetime = timezone.make_aware(end_datetime)
+        self.create_model(start_datetime, end_datetime)
+        self.create_model(end_datetime, start_datetime)
+
+        msg = "Invalid lookup_name: "
+        with self.assertRaisesMessage(ValueError, msg):
+            DTModel.objects.filter(
+                start_datetime__year=Extract(
+                    "start_datetime", "day' FROM start_datetime)) OR 1=1;--"
+                )
+            ).exists()
+
     def test_extract_func(self):
         start_datetime = datetime(2015, 6, 15, 14, 30, 50, 321)
         end_datetime = datetime(2016, 6, 15, 14, 10, 50, 123)
@@ -620,6 +637,23 @@ def test_extract_second_func(self):
         )
         self.assertEqual(DTModel.objects.filter(start_datetime__second=ExtractSecond('start_datetime')).count(), 2)
 
+    def test_trunc_lookup_name_sql_injection(self):
+        start_datetime = datetime(2015, 6, 15, 14, 30, 50, 321)
+        end_datetime = datetime(2016, 6, 15, 14, 10, 50, 123)
+        if settings.USE_TZ:
+            start_datetime = timezone.make_aware(start_datetime)
+            end_datetime = timezone.make_aware(end_datetime)
+        self.create_model(start_datetime, end_datetime)
+        self.create_model(end_datetime, start_datetime)
+        msg = "Invalid kind: "
+        with self.assertRaisesMessage(ValueError, msg):
+            DTModel.objects.filter(
+                start_datetime__date=Trunc(
+                    "start_datetime",
+                    "year', start_datetime)) OR 1=1;--",
+                )
+            ).exists()
+
     def test_trunc_func(self):
         start_datetime = datetime(2015, 6, 15, 14, 30, 50, 321)
         end_datetime = datetime(2016, 6, 15, 14, 10, 50, 123)
