InsecureDefaultProtocol.qhelp

<!DOCTYPE qhelp PUBLIC
"-//Semmle//qhelp//EN"
"qhelp.dtd">
<qhelp>
     <overview>
          <p> The <code>ssl</code> library defaults to an insecure version of
          SSL/TLS when no specific protocol version is specified. This may leave
          the connection vulnerable to attack.
          </p>

     </overview>
     <recommendation>

          <p>
            Ensure that a modern, strong protocol is used. All versions of SSL,
            and TLS 1.0 are known to be vulnerable to attacks. Using TLS 1.1 or
            above is strongly recommended. If no explicit
            <code>ssl_version</code> is specified, the default
            <code>PROTOCOL_TLS</code> is chosen. This protocol is insecure and
            should not be used.
          </p>

     </recommendation>
     <example>

       <p>
         The following code shows two different ways of setting up a connection
         using SSL or TLS. They are both potentially insecure because the
         default version is used.
          </p>

          <sample src="examples/insecure_default_protocol.py" />

          <p>
            Both of the cases above should be updated to use a secure protocol
            instead, for instance by specifying
            <code>ssl_version=PROTOCOL_TLSv1_1</code> as a keyword argument.
          </p>
          <p>
            Note that <code>ssl.wrap_socket</code> has been deprecated in
            Python 3.7. A preferred alternative is to use
            <code>ssl.SSLContext</code>, which is supported in Python 2.7.9 and
            3.2 and later versions.
          </p>
     </example>

     <references>
       <li>Wikipedia: <a href="https://en.wikipedia.org/wiki/Transport_Layer_Security"> Transport Layer Security</a>.</li>
       <li>Python 3 documentation: <a href="https://docs.python.org/3/library/ssl.html#ssl.SSLContext"> class ssl.SSLContext</a>.</li>
       <li>Python 3 documentation: <a href="https://docs.python.org/3/library/ssl.html#ssl.wrap_socket"> ssl.wrap_socket</a>.</li>
     </references>

</qhelp>