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Re: [saag] Feedback on Salted EAP draft

Christian Huitema <huitema@microsoft.com> Tue, 14 July 2015 17:50 UTC

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From: Christian Huitema <huitema@microsoft.com>
To: Kathleen Moriarty <kathleen.moriarty.ietf@gmail.com>, Sam Hartman <hartmans-ietf@mit.edu>
Thread-Topic: [saag] Feedback on Salted EAP draft
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Date: Tue, 14 Jul 2015 17:50:33 +0000
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Cc: "saag@ietf.org" <saag@ietf.org>, "emu@ietf.org" <emu@ietf.org>
Subject: Re: [saag] Feedback on Salted EAP draft
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On Tuesday, July 14, 2015 9:01 AM, Kathleen Moriarty wrote:

> Is there interest in reviewing this draft?  Sam pointed out the importance of moving 
> this work forward, it would be helpful to have volunteers to review the work and also 
> to understand the level of interest (if any) before this goes forward as AD sponsored.

The draft is short and clear enough, but it acknowledges a pretty big security issue: "the salted 
password from a compromised database can be used directly to impersonate the client-- there 
is no dictionary attack needed to recover the plaintext password."

That's a pretty big caveat, but there are still some advantages over operating with unsalted passwords. The draft aligns server side password management for EAP-pwd  with standard industry practices, which is good. In case of server compromise, the immediate effect of the compromise is an attack on the already compromised server, and the per-user salt make password discovery harder. The security section should be expanded to explain this tradeoff.

Nits:

- in the abstract, missing "not" in " but did (not?) include support for salted passwords."

-- Christian Huitema

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