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Submission Summary: 0 pending, 8 declined, 2 accepted (10 total, 20.00% accepted)

Submission + - Introducing Shufflecake: Plausible Deniability For Multiple Hidden Filesystems (kudelskisecurity.com)

Gaglia writes: Today we are excited to release Shufflecake, a plausible deniability disc encryption tool aimed at helping people whose freedom of expression is threatened by repressive authorities or dangerous criminal organizations, in particular: whistleblowers, investigative journalists, and activists for human rights in oppressive regimes. Shufflecake is FLOSS (Free/Libre, Open Source Software), source code in C is available and released under the GNU General Public License v3.0 or superior.

You can consider Shufflecake a "spiritual successor" of tools such as Truecrypt and Veracrypt, but vastly improved. First of all, it works natively on Linux, it supports any filesystem of choice, and can manage up to 15 nested volumes per device, so to make deniability of the existence of these partitions really plausible. The reason why this is important versus "simple" disc encryption is best illustrated in the famous XKCD comic 538. You can read more about Shufflecake in this blog post.

More in detail: Shufflecake allows creation of multiple hidden volumes on a storage device in such a way that it is very difficult, even under forensic inspection, to prove the existence of such volumes. Each volume is encrypted with a different secret key, scrambled across the empty space of an underlying existing storage medium, and indistinguishable from random noise when not decrypted. Even if the presence of the Shufflecake software itself cannot be hidden — and hence the presence of secret volumes is suspected — the number of volumes is also hidden. This allows a user to create a hierarchy of plausible deniability, where "most hidden" secret volumes are buried under "less hidden" decoy volumes, whose passwords can be surrendered under pressure. In other words, a user can plausibly "lie" to a coercive adversary about the existence of hidden data, by providing a password that unlocks "decoy" data. Every volume can be managed independently as a virtual block device, i.e. partitioned, formatted with any filesystem of choice, and mounted and dismounted like a normal disc. The whole system is very fast, with only a minor slowdown in I/O throughput compared to a bare LUKS-encrypted disk, and with negligible waste of memory and disc space.

Submission + - Australian PLAID Crypto, ISO Conspiracies, and German Tanks

Gaglia writes: PLAID, the Australian `unbreakable' smart card identification protocol has been recently analyzed in this scientific paper (disclaimer: I am one of the authors, and this is a personal statement.)

Technically, the protocol is a disaster. In addition to many questionable design choices, we found ways for tracing user identities and recover card access capabilities. The attacks are efficient (few seconds on `home' hardware in some cases), and involve funny techniques such as RSA moduli fingerprinting and... German tanks. See this entry on famous Matt Green's crypto blog for a pleasant-to-read explanation.

But the story behind PLAID's standardization is possibly even more disturbing. PLAID was pushed into ISO with a so-called "fast track" procedure. Technical loopholes made it possible to cut off from any discussion the ISO groups responsible for crypto and security analysis. Concerns from tech-savvy experts in the other national panels were dismissed or ignored. We contacted ISO and AusCERT before going public with our paper, but all we got was a questionable and somewhat irate response by PLAID's project editor (our reply here). Despite every possible evidence of bad design, PLAID is now approved as ISO standard, and is coming to you very soon inside security products which will advertise non-existing privacy capabilities.

The detailed story of PLAID in the paper is worth a read, and casts many doubts on the efficacy of the most important standardizing body in the world. It is interesting to see how a "cryptography" product can be approved at ISO without undergoing any real security scrutiny.

On a related note, the enthusiastic comments to PLAID's design made by a few readers in the old Slashdot story reminds us as a cautionary tale that you need cryptographers to assess the security of cryptography. Quoting Bruce Schneier: amateurs produce amateur cryptography.

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