From ccda21561575459f5ec9db889ca21346f13f44bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Mon, 29 Sep 2014 17:23:37 +0200
Subject: [PATCH] Prevent double underscore in safe_eval

CVE-2014-6633
issue4155
review5601002
---
 CHANGELOG                   | 1 +
 trytond/tests/test_tools.py | 2 +-
 trytond/tools/misc.py       | 4 ++--
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 230f4605a6..2958dd0d94 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,4 @@
+* Prevent double underscore in safe_eval (CVE-2014-6633)
 * Add pre-validation on button
 * Model and Field access checked only if _check_access is set
 * Add check_access to RPC
diff --git a/trytond/tests/test_tools.py b/trytond/tests/test_tools.py
index 59393adf34..3a5c3ad4c0 100644
--- a/trytond/tests/test_tools.py
+++ b/trytond/tests/test_tools.py
@@ -64,7 +64,7 @@ class ToolsTestCase(unittest.TestCase):
 
     def test0061safe_eval_getattr(self):
         'Attempt to get arround direct attr access'
-        self.assertRaises(NameError, safe_eval, "getattr(int, '__abs__')")
+        self.assertRaises(NameError, safe_eval, "getattr(int, 'real')")
 
     def test0062safe_eval_func_globals(self):
         'Attempt to access global enviroment where fun was defined'
diff --git a/trytond/tools/misc.py b/trytond/tools/misc.py
index 481d2169a0..ebe7c66209 100644
--- a/trytond/tools/misc.py
+++ b/trytond/tools/misc.py
@@ -369,8 +369,8 @@ def _compile_source(source):
 
 
 def safe_eval(source, data=None):
-    if '__subclasses__' in source:
-        raise ValueError('__subclasses__ not allowed')
+    if '__' in source:
+        raise ValueError('Double underscores not allowed')
 
     comp = _compile_source(source)
     return eval(comp, {'__builtins__': {