TMG’s snaffu

The French company Trident MediaGuard (TMG) specialized in detecting downloads of illegal content has made the headlines. TMG is the company that scouts the net for the French HADOPI. HADOPI is the organism in charge of the graduated response.

In a nutshell, a French expert by the code name of Bluetouff discovered one of TMG’s server with public access. On the server, he found many valuable data such as a password in the clear ( :( ), list of hashes of content to detect, list of IP addresses of detected clients, and executable! He disclosed his discovery here. After that the community analyzed content of the server, and spread it. You may find a good description of the full findings here by cult.of.the.dead.HADOPI (homage to cdc). Among the disclosed data is the a list of IP addresses owned by TMG. No doubt that they will be blacklisted by the major tracker sites.

TMG’s official answer is that this server was a test server and thus having no critical information. Even if this is true, there were some hiccups that a test server should not have, such as a public access or personal information such collected IP addresses.

Lesson: when you are on the side of Law enforcement on the net, you’d better use the best security practice. It is about your credibility.

Thanks to Patrice and Olivier for the good pointers.

PS3 jailbroken v(3)

As I reported, the hacker George Hotz, aka GeoHot, was sued by Sony under DMCA for having leaked the private signing key of PS3.

Sony and GeoHot have settled down an agreement. Under this agreement, GeoHot will never again hack any Sony product. See the official press release by Sony.

Interestingly, during this fight in March, Sony succeeded to get a subpoena that allowed them to have access to every IP address that visited GeoHot’s blog since January 2009.

Predictably Irrational

“Predictably Irrational” from Dan Ariely is not a book about security (neither Sci-Fi). Thus, why do I report about it?

“Predictably Irrational” highlights that many of our reactions are not rational. Every body knows that it is true in extreme conditions. Dan Ariely demonstrates that it is also true in our daily reactions. To prove it, he describes some of the many experiments that he run.

Law 6: You’re the weakest link reminds us that human behaviour is key for security. This book helps to better understand human behaviour. For instance, a full chapter is about honesty. Great to read. This book is a tool to better understand some tricks used by social engineer.

This is related to the latest Bruce Schneier’s pet’s subject societal security.

A book to read.

Stealing cars without difficulty

In the trend to be always more user-friendly, car manufacturers have introduced a new breed of keys : Passive Keyless Entry and Start (PKES) systems. The idea is that the car detects the right key and acts correspondingly. For instance, if your key is in the range of 2 m if will allow to open the door with the handle, if you are inside the car, it will allow to start the engine. And that, of course, with the key in your pocket. you don’t have to push any button. Awfully convenient.

Unfortunately, three researchers from ETH Zürich, Aurélien Francillon, Boris Danev and Srdjan Capkun, have demonstrated a simple attack: a classical relay attack. In PKES, the car is at the initiative of the challenge. They take a first antenna that captures the emission of the car (as the antenna of the key would do) and relay it to a second antenna close to the key (8-10m). The second antenna will act as the car antenna would act. And this is independent of any logical protocol. The two antennas are linked by a cable of RF transmission for longer range. Thus, if you know where the owner of the car is, and can come reasonably near from this owner, you may steal the signal of the key, and thus your accomplice can steal the car. They successfully experimented on real cars.

The recommended countermeasures are to deactivate the key with a switch. This is the worst scenario of countermeasure. You may be sure that people will forget to deactivate the key when leaving their car, or they will forget that they will had deactivated the system and thus will struggle. In nay case, adding a button would annihilate the perceived benefit of this system: being button less. And here is the problem. Unlocking is done without any conscious action of the user.

They propose another countermeasure that is far more complex to implement because it requires to accurately measure the trip time to detect the presence of the relay. And we know how difficult it is (we struggled on that with local control on content in DVB-CPCM).

The problem is that the action is done without the consent of the user, assuming that his presence means access granted. But the car cannot be sure of the actual physical presence.

PS3 jailbroken

Monday, January 24, 2011

At the December CCC conference, George Hotz, by the nickname of GeoHot, disclosed that he has discovered the private key used to sign the firmware of all PS3 devices.

Usually a piece of code is signed using a private key. The device checks that the code is properly signed using the corresponding public key. if it is the case, it proves that the software was not tampered and that it was issued by the owner of the private key (here Sony). Normally, there is no way to guess the private key from the public key. The usual assumption is that this private key never ever does leak out. They are usually stored in Hardware Secure Module (HSM) within a safe and with strict security policies. It is the corner-stone assumption of most of the trust models.

It seems that GeoHot and Fail0verflow guessed the private key due to a mistake in the signature software that uses a fixed value and not a true random value, dixit a member of Fail0verflow team in an interview to BBC.

PS3 was already jaibroken. The difference with the previous jailbreak[/url] is that this one is purely software. it does not require to change anything in the PS3.
There is no way to recover. It is now possible to execute any arbitrary code on the PS3, because it is possible to sign any code. The issue is that this checking is done in the loader which cannot be modified in the field (else the hackers could easily change this checking process :( )

Sony has launched, under the DMCA, a procedure of temporary restraining order that attempts to stop dissemination of jailbreak.

Lessons:
– Proper implementation of cryptography is difficult
– PS1 and PS2 were open to homebrew applications. They were never hacked. PS3 was closed… Blocking the access of a game console for homebrew may be an attractor for crackers.

LittleBlackBox project

The LittleBlackBox project does host 2,000 SSL public-private key pairs extracted from gateways, routers…
It seems that some manufacturers did use the same SSL key pair for all the instances of a given hardware and firmware. The project attempts to collect the largest collection of such keys together with the details of corresponding firmware and hardware. Once you know the used keys, it is possible to mount a man in the middle attack. This is clearly the aim of this project.

What is difficult to believe is that many devices share a single key pair. Good security practice requests to use a unique key pair per device. Why should a manufacturer use only one key pair? Most probably because it simplifies the manufacturing. Providing an individual key pair for each box is complex (especially in a “hostile” environment such as a factory). Nevertheless, it is an incredible wrong design decision not to do so. Furthermore, manufacturers can even not revoke the leaked keys because else they would also revoke genuine devices!

Good news for Technicolor’s customers, our devices do not have such flaw.

Lesson: There are some economic-driven decisions that should not be allowed to have secure solutions. Security has a price.

Thanks Patrice for the pointer

Windows Phone 7 jailbreaked

On November 25, Rafael Rivera, Chris Walsh, Long Zheng published an application, ChevronWP7, that unlocked Windows Phone 7. The objective was to be able to install homebrew applications on this platform. The news very quickly was all over the world.

Today, they have removed ChevronWP7 from the distribution. According to their blog,

Earlier today, we were contacted by Brandon Watson, Director of Developer Experience for Windows Phone 7, to discuss the ChevronWP7 unlocking tool.

Through this discussion, we established a mutual understanding of our intent to enable homebrew opportunities and to open the Windows Phone 7 platform for broader access to developers and users.

To pursue these goals with Microsoft’s support, Brandon Watson has agreed to engage in futher discussions with us about officially facilitating homebrew development on WP7. To fast-track discussions, we are discontinuing the unlocking tool effective immediately.

It is the second time that Microsoft is hit quickly after the launching of their products. Beginning of the month, it was for the Kinect, now for WP7. The reaction of Microsoft is interesting. They started discussion before threatening with DMCA (I am not sure that this type of unlocking would be a safe harbor for the recently granted jailbreaking exception. Any lawyer to give an opinion)

One more exploit on the already long list of unlocked devices! We have a tough job!