Re: [perpass] Mail encryption as an example

Russ Housley <> Sat, 17 August 2013 18:25 UTC

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From: Russ Housley <>
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Date: Sat, 17 Aug 2013 14:25:46 -0400
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To: Yaron Sheffer <>
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Subject: Re: [perpass] Mail encryption as an example
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There is a technique for protecting the subject line for S/MIME, but the recipients MUST be exposed for the mail to b delivered.  This exposure can be limited to the clients and various mail servers if SMTP/POP/IMAP are run over TLS.


On Aug 17, 2013, at 7:51 AM, Yaron Sheffer wrote:

> Hi,
> Stephen mentioned that S/MIME is not good enough because headers (to/from) are still exposed. But there's still tons of benefit when the content is encrypted, even if the metadata is exposed (provided users know that it is exposed, of course). E.g. I would like all my internal company email to be encrypted, even if tracing recipients is trivial for the attacker.
> In other words, is the scope of the mailing list/solutions limited to security of individuals, as opposed to organizations?
> From a deployment perspective, I think we know how to provide privacy ("identity protection") only by using heavyweight solutions, such as onion routing. But there's a whole lot of important things we could do (make S/MIME usable, standardize OTR, revive IPsec OE) if we remove this constraint. Are such items in scope of this discussion?
> Thanks,
>    Yaron
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