You can tell that summer is here as the SSL security silly season is just warming up. This is the time of year when we start to get a preview of what will be presented at the annual Black Hat and DEF CON conferences. The season was in full swing when at a recent Black Hat Preview Webcast, noted security expert Ivan Ristic of Qualys, was quoted as stating “we have about 22 million SSL servers with certificates that are completely invalid because they do not match the domain name on which they reside.”
This bold statement alarmed many in the internet security community. Security provider Comodo got so excited, they issued a press release urging Mr. Ristic to “review these figures before publishing or presenting this to an informed audience.” In his blog post, Mr. Ristic refuted the alleged quotes and stated “they’ve generally focused on the wrong aspect of the study and that, in fact, I made no such sensational claims.” He went on to clarify as follows:
The important number is the 720,000 certificates whose names do match the domain names on which they reside. For each of those, someone made an effort to match the names, and those are the servers that are worth investigating further.
Sadly, some people chose to focus on the numbers that help make an interesting headline, but which aren’t very interesting from the research point of view. The reason we have so many domain names that do not have proper SSL certificates installed is that most of them are not _intended_ to have them. Multiple domain names will point to the same IP address and, thus, to the same SSL server. (Remember, virtual SSL hosting is not yet mainstream.) The difference in numbers is because of the widespread use of virtual web hosting, which is available for non-SSL sites, but not yet for SSL sites. You can host a million plain-text web sites on a single IP address, but if you want a million secure sites, you’d need a million IP addresses.
We in the SSL industry are getting used to the Black Hat and DEF CON excitement at this time of year. The last two years have provided SSL security “revelations” from respected researchers Dan Kaminsky, Michael Zusman, and Moxie Marlinspike. This year should be no exception with talks from Ivan Ristic at Black Hat 2010 and from Peter Eckersley at DEF CON 18.
At Entrust, we look forward to the silly season. The security experts draw their line in the sand, throw down the gauntlet, and we as security providers must review and respond. It keeps us sharp. Its healthy. As such, we’ll keep an eye on the goings on at Black Hat and DEF CON and will respond accordingly.