On Jul 27, 2010, at 3:34 PM, Ben Laurie wrote: > On 24/07/2010 18:55, Peter Gutmann wrote: >> - PKI dogma doesn't even consider availability issues but expects the >> straightforward execution of the condition "problem -> revoke cert". For a >> situation like this, particularly if the cert was used to sign 64-bit >> drivers, I wouldn't have revoked because the global damage caused by that is >> potentially much larger than the relatively small-scale damage caused by the >> malware. So alongside "too big to fail" we now have "too widely-used to >> revoke". Is anyone running x64 Windows with revocation checking enabled and >> drivers signed by the Realtek or JMicron certs? > > One way to mitigate this would be to revoke a cert on a date, and only > reject signatures on files you received after that date.
I like that idea, as long as a verifiable timestamp is included. Without a trusted timestamp, would the bad guy be able to backdate the signature? Paul Tiemann (DigiCert) --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com