A practical key-recovery attack on LWE-based key-encapsulation mechanism schemes using Rowhammer

Physical attacks are serious threats to cryptosystems deployed in the real world. In this work, we propose a microarchitectural end-to-end attack methodology on generic lattice-based post-quantum key encapsulation mechanisms to recover the long-term secret key. Our attack targets a critical component of a Fujisaki-Okamoto transform that is used in the construction of almost all lattice-based key encapsulation mechanisms. We demonstrate our attack model on practical schemes such as Kyber and Saber by using Rowhammer. We show that our attack is highly practical and imposes little preconditions on the attacker to succeed. As an additional contribution, we propose an improved version of the plaintext checking oracle, which is used by almost all physical attack strategies on lattice-based key-encapsulation mechanisms. Our improvement reduces the number of queries to the plaintext checking oracle by as much as $39\%$ for Saber and approximately $23\%$ for Kyber768. This can be of independent interest and can also be used to reduce the complexity of other attacks

A practical key-recovery attack on LWE-based key- encapsulation mechanism schemes using Rowhammer

Physical attacks are serious threats to cryptosystems deployed in the real world. In this work, we propose a microarchitectural end-to-end attack methodology on generic lattice-based post-quantum key encapsulation mechanisms to recover the long-term secret key. Our attack targets a critical component of a Fujisaki-Okamoto transform that is used in the construction of almost all lattice-based key encapsulation mechanisms. We demonstrate our attack model on practical schemes such as Kyber and Saber by using Rowhammer. We show that our attack is highly practical and imposes little preconditions on the attacker to succeed. As an additional contribution, we propose an improved version of the plaintext checking oracle, which is used by almost all physical attack strategies on lattice-based key-encapsulation mechanisms. Our improvement reduces the number of queries to the plaintext checking oracle by as much as 39% for Saber and approximately 23% for Kyber768. This can be of independent interest and can also be used to reduce the complexity of other attacks

Cross-over between magnetic and electric edges in quantum Hall systems

We report on the transition from magnetic edge to electric edge transport in a split magnetic gate device which applies a notch magnetic field to a two-dimensional electron gas. The gate bias allows tuning the overlap of magnetic and electric edge wavefunctions on the scale of the magnetic length. Conduction at magnetic edges - in the 2D-bulk - is found to compete with conduction at electric edges until magnetic edges become depleted. Current lines then move to the electrostatic edges as in the conventional quantum Hall picture. The conductivity was modelled using the quantum Boltzmann equation in the exact hybrid potential. The theory predicts the features of the bulk-edge cross-over in good agreement with experiment.Comment: latex file, four figures( Experiment and Theory) , Rapid Communication ( supplementary information available at https://journals.aps.org/prb/supplemental/10.1103/PhysRevB.96.081302 or upon request

Cellulosic fibre drying: fundamental understanding and process modeling

[EN] Process modeling of conveyer dryer for cellulosic fibre drying demands many fundamental insights. Present study highlights detailed cellulosic fibre drying aspects like mass transfer correlation relating mass transfer rate with process conditions, normalized drying curve and critical moisture content. Cellulosic fibre drying follows falling rate period, where rate of mass transfer decreases with moisture content. Conveyer dryer process model for commercial cellulosic fibre drying was developed and validated successfully. Moderate drying strategy derived based on developed process model and drying fundamentals was deployed at commercial scale which helped in reducing the moisture variability.This work is supported by Grasim Industries, Aditya Birla Group. Authors are thankful to ABSTCPL leadership and other team members for their valuable inputs during this project.Mondal, S.; Agarwala, P.; Dutta, S.; Naik-Nimbalkar, V.; Pande, P.; Dhumal, S. (2018). Cellulosic fibre drying: fundamental understanding and process modeling. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 627-634. https://doi.org/10.4995/IDS2018.2018.7384OCS62763

Novel positron emission tomography radiotracers in brain tumor imaging

Although [18F] 2-fluoro-2-deoxy-D-glucose (FDG) is the most widely used radiopharmaceutical the world over, it is not the ideal tracer for brain imaging, owing to its high physiological cortical uptake and lack of specificity. This has paved the way for the introduction of several novel radiotracers, each with their own inherent strengths and limitations. We present the insights gained from the use of these radiotracers at our institution