TLS Alert - Wrong version number in version 0.6.

[burgerzoid]

We are running sslyze 0.6 and are overall very happy with it, however we are getting errors checking SSL certs on certain web servers.

The problem is response of:
certinfo exception="utils.SSLyzeSSLConnection.SSLHandshakeRejected - TLS Alert - Wrong version number"

This only occurs when checking a small number of HTTPS servers.

I realise this is an old version, and the problems we are having may have been resolved in more current releases, however at the moment we are not able to upgrade due to the version of python (2.6) on our monitoring servers.

Are you able to provide any advice on how we could resolve this while continuing to run version 0.6?

[nabla-c0d3]

It most likely has to do with the fact that 0.6 doesn't try to find which TLS version the server will accept - it just always uses TLS 1.0 even if the server doesn't support it:
https://github.com/nabla-c0d3/sslyze/blob/ctypes-openssl-wrapper/plugins/PluginCertInfo.py#L354

You would have to first try a bunch of versions and figure out which one to use like here in the current version of sslyze:
https://github.com/nabla-c0d3/sslyze/blob/master/utils/ServersConnectivityTester.py#L226