Adobe @ CanSecWest 2015

Along with other members of the ASSET team, I recently attended CanSecWest 2015, an annual security conference held in Vancouver, Canada.  Pwn2Own is also co-located in the same venue as CanSecWest (a summary of this year’s results can be found here).  This was my first time attending CanSecWest and I found that I enjoyed the single-track style of the conference (it reminded me of the IEEE Symposium on Security and Privacy, which is also a small, single-track conference, though more academic in content).

Overall, there were some great presentations.  “I see, therefore I am… You” presented by Jan “starbug” Krissler of T-Labs/CCC (abstract listed here) detailed methods of using high resolution images to create techniques for authenticating to biometric systems, such as fingerprint readers, iris scanners, and facial recognition systems.  Given the advancements in high resolution cameras, the necessary base images can even be taken from a distance.  One can also use high resolution still images, such as from political campaign posters, or high resolution video.  Using such images, in some cases one can directly authenticate to the biometric system.  In one example, the face recognition software required the user to blink or move before unlocking the system (presumably to avoid unlocking simply for still images); however, Jan found that if you hold a printed image of the user’s face in front of the camera and simply swipe a pencil down and up across the face, then the system will unlock.  Overall, this presentation was insightful, engaging, and generally amusing.  It highlights how more effort needs to be placed on improving the security of biometric systems and that they are not yet ready to be solely relied upon for authentication. I recommend that those interested in biometric security watch this presentation once the recording is available (NOTE: there is one slide that some may find objectionable).

The last day of the conference had multiple talks about BIOS and UEFI security.  The day was kicked off with the presentation entitled “How many million BIOSes would you like to infect?” presented by Corey Kallenberg and Xeno Kovah of LegbaCore (abstract listed here, slides available here).  They showed how their “LightEater” System Management Mode (SMM) malware implant could operate with very high privilege and read everything from memory in a manner undetectable to the OS.  They demonstrated this live on multiple laptops, including a “military grade” MSI system that was running Tails via live boot.  This could be used to steal GPG keys, passwords, or decrypted messages.  They also showed how Serial-over-LAN could be used to exfiltrate data, including the ability to encrypt the data so as to bypass intrusion detection systems that are looking for certain signatures to identify this type of exploit.  Their analysis showed that UEFI systems share similar code, meaning that many BIOSes are vulnerable to being hooked and implanted with LightEater.  The aim of their presentation was to show that more attention should be put forth towards BIOS security.

When conducting application security reviews, threat modeling is used to understand the overall system and identify potential weakness in the security posture of the system.  The security techniques used to address those weakness, also rely on some root of trust, be that a CA or the underlying local host/OS.  This presentation highlights that when your root of trust is the local host and you are the victim of a targeted attack, then the security measures you defined may be inadequate.  Using defense in depth techniques along with other standard security best practices when designing your system can help minimize the impact of such techniques (for instance, using service-to-service authentication mechanisms that have an expiry, are least privileged, and limit server-side the source location of the client, so that if this exploit happens to the host, the service authentication token is not useful from an external network).

Todd Baumeister
Web Security Researcher

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