This thread is amazing. I've known just a fractions/hints of the practices described here. Few comments/questions inline/below. On 12/04/11 07:37, Lucky Green wrote:
Concur. The standard sub-CA contracts contain a right to audit the number of certs issued, like any enterprise-wide software license agreement does include a right to audit used seats. Not once in over 30 years have I seen such an audit performed. There is no reason to audit: when you buy a sub-CA, the public CA's rep will work out a contract that gives you the right to use as many certs and more as you conceivably could use given the application to which you plan to put the sub-CAs. Keeping count of actual certs issued would only add cost to both the sub-CA customer and the root CA provider. There is simply no business case for auditing the number of certs issued.
On 12/02/11 11:02, Peter Gutmann wrote:
It's not just a claim, I've seen them too. For example I have a cert issued for google.com from such a MITM proxy. I was asked by the contributor not to reveal any details on it because it contains the name and other info on the intermediate CA that issued it, but it's a cert for google.com used for deep packet inspection on a MITM proxy. I also have a bunch of certs from private- label CAs that chain directly up to big-name public CAs, there's no technical measure I can see in them anywhere that would prevent them from issuing certs under any name.
How do MitM boxes react when they MitM connection to a server with self-signed
cert (or cert issued by an obsure CA not trusted by MitM box)? Do the boxes send
to client also an auto-generated self-signed cert that generates warning or
"re-sign" it so that client sees valid chain?
MitM-re-signing an unverifiable chain of server to a chain that's trusted at the
MitM-ed client would be hilarious, allowing to MitM a MitM box (though this
would be an easily avoidable mistake to make).
Given the state of security/auditing of "private sub-CAs" as described, was
there ever a report of a breach (e.g. stolen key, fraudulently issued certs)?