CAT | China
The short version is, if an attacker is going for you specifically, they can do enough research to craft an email and attachment that you are almost certain to open. The success rate against even very paranoid and sophisticated users is shockingly high.
In Bruce Schneier’s blog post about this he quotes Brian Snow, former NSA Information Assurance Director. “Your cyber systems continue to function and serve you not due to the expertise of your security staff but solely due to the sufferance of your opponents.”
It appears that China recently launched a poorly executed Man in the Middle (MITM) attack on GitHub.
GitHub.com is an https only website, so the only way to monitor it is to use a MITM attack to decrypt the contents of the communications. There is evidence that GitHub is widely used in China for code sharing, so the backlash from blocking it completely was too large, and it was unblocked a few days later.
The attack happened on January 26. It was poorly executed in that the faked certificate did not match the real one in any of the meta-data and it was not signed by a recognized certificate authority. This caused most browsers to report a security error. The MITM attack only lasted about an hour.
Based on reports it only impacted users in China, which strongly suggests that it was government backed at some level. My work in censorship circumvention over the years has shown that China is far from monolithic. This could have been the work of a local government or regional ISP. I have not seen an analysis showing if this was country wide or not. It seems very ham fisted for the central government.
The speculated reason for the attack is to monitor access to a list of people who have been involved in creating the Great Firewall of China, which is hosted on GitHub, and is connected to a petition on Whitehouse.gov proposing that those people be denied entry to the US.
In the tradition of Jonathan Swift’s “A Modest Proposal” is “The Dictator’s Practical Guide to Internet Power Retention, Global Edition”.
Under the pretext of being a guide on how to crack down on Internet dissent for dictators, it does a nice job of analyzing how the Internet is used by dissidents, and the techniques used by governments to crack down on those practices.
Thanks to boingboing for bringing this to my attention.
This article from Threatpost discusses a study out of CMU of Chinese censorship of their home grown social networking websites.
Now that they are blocking most of the western social media sites entirely, the focus of censorship is internal. Obviously blocking the internal sites as well would defeat the purpose, so they are selectively deleting posts instead. This study looks at the rate at which posts with sensitive key words are removed from the services.
It clearly shows how censorship can be taken to the next level when the censor controls the websites as well as the network.
I have been reading about this “Haystack” anti-censorship tool for a while, but have withheld comment up to now. The above linked article seems to justify my reticence.
This tool has been a media darling, hyped in many different publications, but try as I might I have never been able to find out any solid information about what it actually does. Just a lot of marketing hype.
It now looks like the system was well intentioned snake oil. I still have not seen it, so this is all hearsay. Unfortunately it can be very difficult for the average person to tell the difference. One thing to look for is transparency in security systems. No security system should rely on assuming the enemy will not work out how it operates. It absolutely must be secure even if the opponent knows everything.
Other good signs are the experience and reputation of the author, the length of time the tool has been in use, and published analysis by other independent security experts.
As it turns out, media hype has a very poor correlation with real security.