For IE and other things using CryptoAPI on Windows, this should be handled through the automagic root certificate update through Windows Update (if one hasn't disabled it), AFAIK.
The question is really whether that mechanism requires a cert rooted at a Microsoft authority or not. The danger being that someone could use an intermediate CA rooted at an md5-signing CA and present a seemingly valid cert through that with the right common name. Some other Microsoft things (i.e. KMCS) require certs rooted to a single specific root and not just *any* global root, so it's possible that the same is done for root certificate update blobs; however, I don't know for certain, and some research would need to be done. I don't think any of the MS issuing roots use md5, though. - S -----Original Message----- From: Deepak Jain [mailto:dee...@ai.net] Sent: Friday, January 02, 2009 4:14 PM To: Steven M. Bellovin Cc: NANOG Subject: RE: Security team successfully cracks SSL using 200 PS3's and MD5 flaw. > If done properly, that's actually an easier task: you build the update > key into the browser. When it pulls in an update, it verifies that it > was signed with the proper key. > If you build it into the browser, how do you revoke it when someone throws 2000 PS3s to crack it, or your hash, or your [pick algorithmic mistake here]. Deepak
