Add random.randbytes to blacklist calls (#1096)

In Python 3.9, the random module added new function randbytes(n). This function shouldn't be used for any cryptographic operations. As the doc recommends, use secrets.token_bytes() instead. https://docs.python.org/3/library/random.html#random.randbytes Signed-off-by: Eric Brown <eric_wade_brown@yahoo.com>
PyCQA · Jan 19, 2024 · 0779eb0 · 0779eb0
1 parent 7129108
commit 0779eb0
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Showing 3 changed files with 5 additions and 2 deletions.
diff --git a/bandit/blacklists/calls.py b/bandit/blacklists/calls.py
@@ -198,6 +198,7 @@
 |      |                     | - random.choices                   |           |
 |      |                     | - random.uniform                   |           |
 |      |                     | - random.triangular                |           |
+|      |                     | - random.randbytes                 |           |
 +------+---------------------+------------------------------------+-----------+
 
 B312: telnetlib
@@ -523,6 +524,7 @@ def gen_blacklist():
                 "random.choices",
                 "random.uniform",
                 "random.triangular",
+                "random.randbytes",
             ],
             "Standard pseudo-random generators are not suitable for "
             "security/cryptographic purposes.",

diff --git a/examples/random_module.py b/examples/random_module.py
@@ -10,6 +10,7 @@
 bad = random.choices()
 bad = random.uniform()
 bad = random.triangular()
+bad = random.randbytes()
 
 good = os.urandom()
 good = random.SystemRandom()

diff --git a/tests/functional/test_functional.py b/tests/functional/test_functional.py
@@ -396,8 +396,8 @@ def test_popen_wrappers(self):
     def test_random_module(self):
         """Test for the `random` module."""
         expect = {
-            "SEVERITY": {"UNDEFINED": 0, "LOW": 8, "MEDIUM": 0, "HIGH": 0},
-            "CONFIDENCE": {"UNDEFINED": 0, "LOW": 0, "MEDIUM": 0, "HIGH": 8},
+            "SEVERITY": {"UNDEFINED": 0, "LOW": 9, "MEDIUM": 0, "HIGH": 0},
+            "CONFIDENCE": {"UNDEFINED": 0, "LOW": 0, "MEDIUM": 0, "HIGH": 9},
         }
         self.check_example("random_module.py", expect)