SSL 3.0 on Splat

[vijayiyer]

Web Service (https) running on the SecurePlatform Management Server, Gateways modules and Eventia Servers encrypts traffic using SSL 2.0, can it use SSL 3.0 or TLS 1.0 instead ?

Vijay

[chillyjim]

No it doesn't. It initially opens the page with V2 so a non-TLS browser can be notified that it needs to upgrade, then it will switch to TLS.

This is something I received from RnD a while ago, and posted here before:

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"The question here is not of support for SSLv3. We support SSLv3 as well as
the more advanced TLS. The problem here is that we also support SSLv2,
which is less secure. A web browser can connect to a SPLAT gateway using
any of these protocol versions.

In additions to these three protocol versions, there is also a transition
version, where the client sends the first message of SSLv2 (called "Client
Hello") with an attribute that says that it actually supports SSLv3 or TLS.
In that case, the server may either reply using SSLv3 (or TLS) or stay with
SSLv2 depending on its configuration.

The HTTPS server that was scanned supports all 4 modes.

We have considered totally removing support for SSLv2, and supporting only
SSLv3 and TLS. However, this is a bad idea, because Internet Explorer by
default uses the transition (SSLv2 client hello with support for SSLv3, but
no TLS).

Since we can't disable SSLv2, we've done the next best thing. We let the
SSL protocol run, and close the connection if it did not end up as SSLv3 or
TLS. This has the effect of preventing the insecure SSLv2, while still
allowing Internet Explorer to run. Windows Vista and probably some future
Windows XP service pack will have SSLv2 disabled. When this becomes common
enough, we may be able to totally disable SSLv2.

To sum things up:
- R55 allows SSLv2
- NGX only allows SSLv2 for the transition.

One further note: Even in NGX all the SSLv2 negotiation can pass before the
connection is broken. This has no security implication, but may trick Nessus
into reporting that SSLv2 is supported. To demonstrate that this is not so,
you can configure Internet Explorer to support only SSLv2 (uncheck "Use SSL
3.0" under Tools->Internet Options...->Advanced->Security) and try to
connect to the gateway.

[vijayiyer]

Thanks for the reply and the information.

vijay