fix(common): prevent injection during jinja templating (v2.23)

tests/test_common.py

@@ -1,5 +1,6 @@
 from datetime import date, datetime, timedelta
 
+import jinja2
 import numpy as np
 import pandas as pd
 import pytest
@@ -254,6 +255,21 @@ def test_nosql_apply_parameters_to_query(query, params, expected):
     assert nosql_apply_parameters_to_query(query, params) == expected
 
 
+def test_nosql_apply_parameters_to_query_unsafe():
+    """
+    It should prevent any code execution, by using Jinja's sandboxed environement
+    """
+    with pytest.raises(jinja2.exceptions.SecurityError):
+        nosql_apply_parameters_to_query(
+            {
+                'test': "{% for x in var.__class__.__base__.__subclasses__() %}{% if 'warning' in x.__name__ %}{{x()._module.__builtins__ ['__import__']('os').popen('ls').read()}}{% endif %}{% endfor %}"
+            },
+            {'var': 'plop'},
+        )
+    with pytest.raises(jinja2.exceptions.SecurityError):
+        nosql_apply_parameters_to_query({'test': '{{ var.__class__.mro()[-1] }}'}, {'var': 'plop'})
+
+
 def test_nosql_apply_parameters_to_query_dot():
     """It should handle both `x["y"]` and `x.y`"""
     query1 = {'facet': '{{ facet.value }}', 'sort': '{{ rank[0] }}', 'rows': '{{ bibou[0].value }}'}

toucan_connectors/common.py

@@ -11,11 +11,17 @@
 import jq
 import pandas as pd
 from aiohttp import ClientSession
-from jinja2 import Environment, StrictUndefined, Template, meta
+from jinja2 import StrictUndefined, Template, meta
 from jinja2.nativetypes import NativeEnvironment
+from jinja2.sandbox import ImmutableSandboxedEnvironment
 from pydantic import Field
 from toucan_data_sdk.utils.helpers import slugify
 
+
+class NativeImmutableSandboxedEnvironment(NativeEnvironment, ImmutableSandboxedEnvironment):
+    ...
+
+
 # Query interpolation
 
 RE_PARAM = r'%\(([^(%\()]*)\)s'
@@ -62,7 +68,7 @@ def is_jinja_alone(s: str) -> bool:
 
 
 def _has_parameters(query: dict | list[dict] | tuple | str) -> bool:
-    t = Environment().parse(query)
+    t = ImmutableSandboxedEnvironment().parse(query)
     return bool(meta.find_undeclared_variables(t) or re.search(RE_PARAM, query))
 
 
@@ -129,9 +135,9 @@ def _render_query(query: dict | list[dict] | tuple | str, parameters: dict):
             clean_p = _prepare_parameters(clean_p)
 
         if is_jinja_alone(query):
-            env = NativeEnvironment()
+            env = NativeImmutableSandboxedEnvironment()
         else:
-            env = Environment()
+            env = ImmutableSandboxedEnvironment()
 
         res = env.from_string(query).render(clean_p)
         # NativeEnvironment's render() isn't recursive, so we need to

toucan_connectors/snowflake/snowflake_connector.py

@@ -11,7 +11,7 @@
 import pandas as pd
 import requests
 import snowflake
-from jinja2 import Template
+from jinja2.sandbox import ImmutableSandboxedEnvironment
 from pydantic import Field, SecretStr, create_model
 from snowflake.connector import SnowflakeConnection
 
@@ -220,7 +220,7 @@ def get_status(self) -> ConnectorStatus:
 
     def get_connection_params(self):
         params = {
-            'user': Template(self.user).render(),
+            'user': ImmutableSandboxedEnvironment().from_string(self.user).render(),
             'account': self.account,
             'authenticator': self.authentication_method,
             # hard Snowflake params