Freezer-based attack on Android encryption
I believe in the software security industry they talk about ‘vectors of attack’, well how about a Freezer-based vector of attack?
The Register is among those reporting a technique to surmount the built-in disk encryption that has been part of Android since version 4.0 (“Ice Cream Sandwich”). It partly involves freezing a device to below 10°C, and taking advantage of a ‘Remanence Effect’.
The title cites a research paper by Tilo Müller, Michael Spreitzenbarth, and Felix Freiling of the Friedrich-Alexander University of Erlangen-Nuremberg (FAU) in Germany. Their data recovery tool is dubbed FROST (Forensic Recovery of Scrambled Telephones), and they used (Samsung) Galaxy Nexus devices for testing.
The Android encryption is not enabled by default and, crucially, the reduction in temperature allows – for a short time period – a glimpse of the original status of the RAM. Interesting….
Read the full post – Boffins FREEZE PHONES to crack Android on-device crypto
The abstract for the academic paper reads:
At the end of 2011, Google released version 4.0 of its Android operating system for smartphones. For the first time, Android smartphone owners were supplied with a disk encryption feature that transparently encrypts user partitions. On the downside, encrypted smartphones are a nightmare for IT forensics and law enforcement, because brute force appears to be the only option to recover encrypted data by technical means. However, RAM contents are necessarily left unencrypted and, as we show, they can be acquired from live systems with physical access only. To this end, we present the data recovery tool Frost (Forensic Recovery of Scrambled Telephones). Using Galaxy Nexus devices from Samsung as an example, we show that it is possible to perform cold boot attacks against Android smartphones and to retrieve valuable information from RAM. This information includes personal messages, photos, passwords and even the encryption key. Since smartphones get switched off only seldom, and since the tools that we provide must not be installed before the attack, our method can be applied in real cases.
[Source: Department of Computer Science, Friedrich-Alexander University of Erlangen-Nuremberg]