Multi-Bit Differential Fault Analysis of Grain-128 with Very Weak Assumptions

Very few differential fault attacks (DFA) were reported on {\em Grain-128} so far. In this paper we present a generic attack strategy that allows the adversary to challenge the cipher under different multi-bit fault models with faults at a targeted keystream generation round even if bit arrangement of the actual cipher device is unknown. Also unique identification of fault locations is not necessary. To the best of our knowledge, this paper assumes the weakest adversarial power ever considered in the open literature for DFA on {\em Grain-128} and develops the most realistic attack strategy so far on {\em Grain-128}. In particular, when a random area within $k \in \{1,2,3,4,5\}$ neighbourhood bits can only be disturbed by a single fault injection at the first keystream generation round ($k$-neighbourhood bit fault), without knowing the locations or the exact number of bits the injected fault has altered, our attack strategy always breaks the cipher with $5$ faults. In a weaker setup even if bit arrangement of the cipher device is unknown, bad-faults (at the first keystream generation round) are rejected with probabilities $0.999993$, $0.999979$, $0.999963$, $0.999946$ and $0.999921$ assuming that the adversary will use only 1, 2, 3, 4 and 5 neighbourhood bit faults respectively for {\em key-IV} recovery

Molecular enneanuclear CuII phosphates containing planar hexanuclear and trinuclear sub-units: syntheses, structures, and magnetism

Highly symmetric enneanuclear copper(II) phosphates [Cu9(Pz)6(μ-OH)3(μ3-OH)(ArOPO3)4(DMF)3] (PzH =pyrazole, Ar = 2,6-(CHPh2)2-4-R-C6H2; R = Me, 2MeAr; Et, 2EtAr; iPr, 2iPrAr; and Ar = 2,6-iPr2C6H3, 2Dip) comprising nine copper(II) centers and pyrazole, hydroxide and DMF as ancillary ligands were synthesized by a reaction involving the arylphosphate monoester, 1, copper(I)chloride, pyrazole, and triethylamine in a 4 : 9 : 6 : 14 ratio. All four complexes were characterized by single crystal structural analysis. The complexes contain two distinct structural motifs within the multinuclear copper scaffold: a hexanuclear unit and a trinuclear unit. In the latter, the three Cu(II) centres are bridged by a µ3-OH. Each pair of Cu(II) centers in the trinuclear unit are bridged by a pyrazole ligand. The hexanuclear unit is made up of three dinuclear Cu(II) motifs where the two Cu(II) centres are bridged by an -OH and a pyrazole ligand. The three dinuclear units are connected to each other by phosphate ligands. The latter also aid the fusion of the trinuclear and the hexanuclear motifs. Magnetic studies reveal a strong antiferromagnetic exchange between the Cu(II) centres of the dinuclear units in the hexanuclear part and a strong spin frustration in the trinuclear part leading to a degenerate ground state

Safe is the new Smart: PUF-based Authentication for Load Modification-Resistant Smart Meters

In the energy sector, IoT manifests in the form of next-generation power grids that provide enhanced electrical stability, efficient power distribution and utilization. The primary feature of a Smart Grid is the presence of an advanced bi-directional communication network between the Smart meters at the consumer end and the servers at the Utility Operators. The Smart meters are broadly vulnerable to attacks on communication and physical systems. We propose a secure and operationally asymmetric mutual authentication and key-exchange protocol for secure communication. Our protocol balances security and efficiency, delegates complex cryptographic operations to the resource-equipped servers, and carefully manages the workload on the resource-constrained Smart meter nodes using unconventional lightweight primitives such as Physically Unclonable Functions. We prove the security of the protocol using well-established cryptographic assumptions. We implement the proposed scheme end-to-end in a Smart meter prototype using commercial-off-the-shelf products, a Utility server and a credential generator as the trusted third party. Additionally, we demonstrate a physics-based attack named load modification attack on the Smart meter to demonstrate that merely securing the communication channel using authentication does not secure the meter, but requires further protections to ensure the correctness of the reported consumption. Hence, we propose a countermeasure to such attack that goes side-by-side with our protocol implementation.ISSN:1545-5971ISSN:1941-001

Density of CD3+ and CD8+ cells in gingivo-buccal oral squamous cell carcinoma is associated with lymph node metastases and survival.

The tumor immune microenvironment is emerging as a critical player in predicting cancer prognosis and response to therapies. However, the prognostic value of tumor-infiltrating immune cells in Gingivo-Buccal Oral Squamous Cell Carcinoma (GBOSCC) and their association with tumor size or lymph node metastases status require further elucidation. To study the relationship of tumor-infiltrating immune cells with tumor size (T stage) and lymph node metastases (N stages), we analyzed the density of tumor-infiltrating immune cells in archived, whole tumor resections from 94 patients. We characterized these sections by immune-histochemistry using 12 markers and enumerated tumor-infiltrating immune cells at the invasive margins (IM) and centers of tumors (CT). We observed that a higher density of CD3+ cells in the IM and CT was associated with smaller tumor size (T1-T2 stage). Fewer CD3+ cells was associated with larger tumor size (T3-T4 stage). High infiltration of CD3+and CD8+ cells in IM and CT as well as high CD4+ cell infiltrates in the IM was significantly associated with the absence of lymph node metastases. High infiltrates of CD3+ and CD8+ cells in CT was associated with significantly improved survival. Our results illustrate that the densities and spatial distribution of CD3+ and CD8+ cell infiltrates in primary GBOSCC tumors is predictive of disease progression and survival. Based on our findings, we recommend incorporating immune cell quantification in the TNM classification and routine histopathology reporting of GBOSCC. Immune cell quantification in CT and IM may help predict the efficacy of future therapies

Towards Secure Composition of Integrated Circuits and Electronic Systems: On the Role of EDA

International audienceModern electronic systems become evermore complex, yet remain modular, with integrated circuits (ICs) acting asversatile hardware components at their heart. Electronic design automation (EDA) for ICs has focused traditionally on power, performance, and area. However, given the rise of hardwarecentric security threats, we believe that EDA must also adopt related notions like secure by design and secure composition of hardware. Despite various promising studies, we argue that some aspects still require more efforts, for example: effective means for compilation of assumptions and constraints for security schemes, all the way from the system level down to the “bare metal”; modeling, evaluation, and consideration of securityrelevant metrics; or automated and holistic synthesis of various countermeasures, without inducing negative cross-effects. In this paper, we first introduce hardware security for the EDA community. Next we review prior (academic) art for EDA-driven security evaluation and implementation of countermeasures. We then discuss strategies and challenges for advancing research and development toward secure composition of circuits and systems