On Fri, Aug 8, 2008 at 5:57 PM, Eric Rescorla <ekr@xxxxxxxxxxxxxxxxxxxx> wrote: > At Fri, 8 Aug 2008 17:31:15 +0100, > Dave Korn wrote: >> >> Eric Rescorla wrote on 08 August 2008 16:06: >> >> > At Fri, 8 Aug 2008 11:50:59 +0100, >> > Ben Laurie wrote: >> >> However, since the CRLs will almost certainly not be checked, this >> >> means the site will still be vulnerable to attack for the lifetime of >> >> the certificate (and perhaps beyond, depending on user >> >> behaviour). Note that shutting down the site DOES NOT prevent the attack. >> >> >> >> Therefore mitigation falls to other parties. >> >> >> >> 1. Browsers must check CRLs by default. >> > >> > Isn't this a good argument for blacklisting the keys on the client >> > side? >> >> Isn't that exactly what "Browsers must check CRLs" means in this context >> anyway? What alternative client-side blacklisting mechanism do you suggest? > > It's easy to compute all the public keys that will be generated > by the broken PRNG. The clients could embed that list and refuse > to accept any certificate containing one of them. So, this > is distinct from CRLs in that it doesn't require knowing > which servers have which cert... It also only fixes this single type of key compromise. Surely it is time to stop ignoring CRLs before something more serious goes wrong?
