Language: Python
Label: vulnerable
CWE: CWE-203 \u2014 Observable Discrepancy
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.

Code:
    def test_it_ignores_bad_tz(self):
        form = {"identity": "alice@example.org", "tz": "Foo/Bar"}

        r = self.client.post("/accounts/signup/", form)
        self.assertContains(r, "Account created")
        self.assertIn("auto-login", r.cookies)

        profile = Profile.objects.get()
        self.assertEqual(profile.tz, "UTC")