RE: RPC over HTTP security

["Depp, Dennis M." <deppdm () ornl gov>]

The "Best" option depends on their business requirements and the amount
of risk they are willing to take.  VPN is a good solution.  To say it is
best in all environments is a bit presumptuous.

Dennis

-----Original Message-----
From: Shawn Wall [mailto:sjwall () shaw ca] 
Sent: Friday, January 28, 2005 4:12 PM
To: Depp, Dennis M.; 'Ansgar -59cobalt- Wiechers';
security-basics () securityfocus com
Subject: RE: RPC over HTTP security

I think your best option is to use a VPN to allow your mobile users
access
to email if they require the functionality of Outlook vs OWA. I've
deployed
this configuration using a PIX and Cisco VPN client. Works very well.

shawn 

-----Original Message-----
From: Depp, Dennis M. [mailto:deppdm () ornl gov] 
Sent: Friday, January 28, 2005 6:19 AM
To: Ansgar -59cobalt- Wiechers; security-basics () securityfocus com
Subject: RE: RPC over HTTP security

Ansgar,

Answers to your questions.

1)  Because the functionality of RPC over HTTP(S) is a great benefit to
mobile users.
2)  It doesn't.  However, by "bloating" the protocol so it will work
over
HTTP, I have also "bloated" the protocol to allow it to work over HTTPS.
This allows me to secure the traffic.

Lets now look at RPC.  What are the major vulnerabilities of RPC?  RPC
does
not authenticate prior to allowing the connection to proceed.  Many of
the
RPC vulnerabilities would be neutered if RPC was force to authenticate
prior
to making the connection.  RPC over HTTP solves this problem by forcing
authentication.  When I add HTTPS to this senario, I have secured my
credentials while they are in an untrusted environment and provided
authentication prior to allowing RPC to proceed.  The RPC traffic is
also
passed through the SSL tunnel providing end-to-end security.

Dennis

-----Original Message-----
From: Ansgar -59cobalt- Wiechers [mailto:bugtraq () planetcobalt net]
Sent: Wednesday, January 26, 2005 8:22 PM
To: security-basics () securityfocus com
Subject: Re: RPC over HTTP security

On 2005-01-26 sf_mail_sbm () yahoo com wrote:
> We are thinking about deploying RPC over HTTP to access email from the

> Internet

Ask yourself two questions:

1. Why does nobody in his right mind do RPC over untrusted networks?
2. How does bloating a protocol by encapsulating it in plain-text make
   it any better?

Regards
Ansgar Wiechers
--
"Those who would give up liberty for a little temporary safety deserve
neither liberty nor safety, and will lose both."
--Benjamin Franklin