Re: [dnsext] DNSSEC, robustness, and several DS records

Paul Hoffman <paul.hoffman@vpnc.org> Thu, 12 May 2011 15:26 UTC

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From: Paul Hoffman <paul.hoffman@vpnc.org>
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To: "W.C.A. Wijngaards" <wouter@nlnetlabs.nl>
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Subject: Re: [dnsext] DNSSEC, robustness, and several DS records
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On May 12, 2011, at 1:20 AM, W.C.A. Wijngaards wrote:

> The weakness in MD5 that I heard about (on slashdot I think) was that
> you could construct data that matched a particular hash.  

You may have heard that on Slashdot; it is wrong. There has been no preimage attack reported on MD5 or SHA1 except on messages that are many terrabytes long, and even those take more than the 2^128 threshold that I proposed earlier.

--Paul Hoffman