To mitigate potential memory safety vulnerabilities, recently there have been significant advances in sanitizers for pre-production bug detection. However, the limited inability to balance performance and detection accuracy still holds. The main reason is due to excessive reliance on shadow memory and a large number of memory access checks at runtime, incurring a significant performance overhead (if fine-grained memory safety detection is performed, the overhead will be even greater). In this paper, we propose a novel Object-Level Address Sanitizer OLASan to reduce performance overhead further while implementing accurate memory violations (including intra-object overflow) detection. Unlike previous sanitizers ignoring the correlation between memory access and objects, OLASan aggregates multiple memory accesses of same object at function level to perform on-demand targeted sanitization, thus avoiding examining most memory accesses at runtime. Specifically, OLASan characterizes various memory access patterns to identify those which can be aggregated, and implements memory safety checks with customized memory tagging. We implement OLASan atop the LLVM framework and evaluate it on SPEC CPU benchmarks. Evaluations show that OLASan outperforms the state-of-the-art methods with 51.18%, 25.20% and 6.52% less runtime overhead than ASan, ASan-- and GiantSan respectively. Moreover, aided by customized memory tagging, OLASan achieves zero false negatives for the first time when testing Juliet suites. Finally, we confirm that OLASan also offers comparable detection capabilities on real bugs.

With the considerable success achieved by modern fuzzing infrastructures, more crashes are produced than ever before. To dig out the root cause, rapid and faithful crash triage for large numbers of crashes has always been attractive. However, hindered by the practical difficulty of reducing analysis imprecision without compromising efficiency, this goal has not been accomplished.

The increasing use of civil unmanned aerial vehicles (UAVs) has the potential to threaten public safety and privacy. Therefore, airspace administrators urgently need an effective method to regulate UAVs. Understanding the meaning and format of UAV flight control commands by automatic protocol reverse-engineering techniques is highly beneficial to UAV regulation. To improve our understanding of the meaning and format of UAV flight control commands, this paper proposes a method to automatically analyze the private flight control protocols of UAVs. First, we classify flight control commands collected from a binary network trace into clusters; then, we analyze the meaning of flight control commands by the accumulated error of each cluster; next, we extract the binary format of commands and infer field semantics in these commands; and finally, we infer the location of the check field in command and the generator polynomial matrix. The proposed approach is validated via experiments on a widely used consumer UAV.

Light encryption device (LED) is a 64 bit lightweight block cipher proposed by Guo et al . at CHES 2011, and its key size is primarily defined as 64 and 128 bits. This study studies differential fault analysis (DFA) of LED using the technique of Super‐Sbox analysis. Under various fault models, the fault pattern propagation rule of the Super‐Sbox can be obtained, based on which the efficiency of fault attack on LED can be greatly improved. For LED‐64, under the nibble‐based fault model, a random nibble fault at the 30th round can reduce the size of key search space to 2 7 –2 20 (average 2 14.02 ). Even if a random nibble fault is injected into the 29th round, the size of the key search space can also be reduced to about 2 17.43 –2 17.72 (average 2 17.65 ) using early‐abort technique. Although under the byte‐based fault model, a random byte fault at the 30th round can reduce the size of the key space to 2 7 –2 16 (average 2 11.92 ). If the adversary has the capability of injecting two random nibble faults at some specified rounds, then the above fault attack on LED‐64 can be similarly extended to LED‐128, and the size of the exhaustive search space for the 128 bit key can be reduced to 2 15 –2 27.94 (average 2 21.96 ). These results demonstrate that Super‐Sbox is a powerful technique that can be used to obtain significant improvements in the key filtration, and thus improve the efficiency of DFA on some special ciphers.

Impossible differential cryptanalysis is a very popular tool for analysing the security of modern block ciphers and the core of such attack is based on the existence of impossible differentials. Currently, most methods for finding impossible differentials are based on the miss-in-the-middle technique and they are very ad hoc. In this study, the authors concentrate on substitution–permutation network (SPN) ciphers whose diffusion layer is defined by a linear transformation P. Based on the theory of linear algebra, the authors propose several criteria on P and its inversion P-1 to characterise the existence of 3/4-round impossible differentials. The authors further discuss the possibility to extend these methods to analyse 5/6-round impossible differentials. Using these criteria, impossible differentials for reduced-round Rijndael are found that are consistent with the ones found before. New 4-round impossible differentials are discovered for block cipher ARIA. Many 4-round impossible differentials are firstly detected for a kind of SPN cipher that employs a 32×32 binary matrix proposed at ICISC 2006 as its diffusion layer. It is concluded that the linear transformation should be carefully designed in order to protect the cipher against impossible differential cryptanalysis.

SHACAL-1, known as one of the finalists of the NESSIE project, originates from the compression component of the widely used hash function SHA-1. The requirements of confusion and diffusion are implemented through mixing operations and rotations other than substitution and permutation, thus there exists little literature on its immunity against fault attacks. In this paper, we apply differential fault analysis on SHACAL-1 in a synthetic approach. We introduce the random word fault model, present some theoretical arguments, and give an efficient fault attack based on the characteristic of the cipher. Both theoretical predications and experimental results demonstrate that, 72 random faults are needed to obtain 512 bits key with successful probability more than 60%, while 120 random faults are enough to obtain 512 bits key with successful probability more than 99%.