Re: [jose] Draft describing encrypting JWK key representations, with JWE

[Adding JOSE mailing list to the thread]

For clarification, PBKDF2 is not the only algorithm that could be used to wrap keys in this scheme.  This draft *adds* PBKDF2 to the set of algorithms already specified for use with encryption in the JSON Web Algorithms (JWA) specification (http://tools.ietf.org/html/draft-ietf-jose-json-web-algorithms-08).  In particular, other algorithms such as AES Key Wrap and AES GCM are also present there.

I'll let others who are experts in PBKDF2 and password-based encryption respond to Yaron's specific comment.

				-- Mike

-----Original Message-----
From: Yaron Sheffer [mailto:yaronf.ietf@gmail.com] 
Sent: Friday, March 15, 2013 8:16 AM
To: cfrg@irtf.org; Mike Jones
Subject: Re: Draft describing encrypting JWK key representations, with JWE

Hi Mike,

I'm probably missing something, but I'm worried about the security of this scheme (though I do appreciate the usability/convenience of passwords).

PBKDF2 is meant to make dictionary attacks on stored passwords harder, as a second line defense, once the server has been breached. Using it to encrypt data and then sending the data on the wire, makes the data vulnerable to this same dictionary attack (in this case the effort comes to the space of all possible passwords - say 1 million - times 1000). 
Moreover, this also puts the password itself in danger.

Thanks,
	Yaron

>
> ------------------------------
>
> Message: 5
> Date: Fri, 15 Mar 2013 14:10:32 +0000
> From: Mike Jones <Michael.Jones@microsoft.com>
> To: "cfrg@irtf.org" <cfrg@irtf.org>
> Subject: [Cfrg] Draft describing encrypting JWK key representations
> 	with JWE
> Message-ID:
> 	
> <4E1F6AAD24975D4BA5B168042967394367522C60@TK5EX14MBXC284.redmond.corp.
> microsoft.com>
> 	
> Content-Type: text/plain; charset="us-ascii"
>
> http://tools.ietf.org/html/draft-miller-jose-jwe-protected-jwk-01
>
> This also adds password-based encryption to the algorithm registry.
>
>                                                              -- Mike
>
> -------------- next part -------------- An HTML attachment was 
> scrubbed...
> URL: 
> <http://www.irtf.org/mail-archive/web/cfrg/attachments/20130315/02e36b
> 24/attachment.htm>
>
> ------------------------------
>
> _______________________________________________
> Cfrg mailing list
> Cfrg@irtf.org
> http://www.irtf.org/mailman/listinfo/cfrg
>
>
> End of Cfrg Digest, Vol 95, Issue 3
> ***********************************
>