HeapRevolver: Delaying and Randomizing Timing of Release of Freed Memory Area to Prevent Use-After-Free Attacks

Recently, there has been an increase in use-after-free (UAF) vulnerabilities, which are exploited using a dangling pointer that refers to a freed memory. Various methods to prevent UAF attacks have been proposed. However, only a few methods can effectively prevent UAF attacks during runtime with low overhead. In this paper, we propose HeapRevolver, which is a novel UAF attack-prevention method that delays and randomizes the timing of release of freed memory area by using a memory-reuse-prohibited library, which prohibits a freed memory area from being reused for a certain period. In this paper, we describe the design and implementation of HeapRevolver in Linux and Windows, and report its evaluation results. The results show that HeapRevolver can prevent attacks that exploit existing UAF vulnerabilities. In addition, the overhead is small

Mitigating Use-After-Free Attacks Using Memory-Reuse-Prohibited Library

Recently, there has been an increase in use-after-free (UAF) vulnerabilities, which are exploited using a dangling pointer that refers to a freed memory. In particular, large-scale programs such as browsers often include many dangling pointers, and UAF vulnerabilities are frequently exploited by drive-by download attacks. Various methods to prevent UAF attacks have been proposed. However, only a few methods can effectively prevent UAF attacks during runtime with low overhead. In this paper, we propose HeapRevolver, which is a novel UAF attackprevention method that delays and randomizes the timing of release of freed memory area by using a memory-reuse-prohibited library, which prohibits a freed memory area from being reused for a certain period. The first condition for reuse is that the total size of the freed memory area is beyond the designated size. The threshold for the conditions of reuse of the freed memory area can be randomized by HeapRevolver. Furthermore, we add a second condition for reuse in which the freed memory area is merged with an adjacent freed memory area before release. Furthermore, HeapRevolver can be applied without modifying the target programs. In this paper, we describe the design and implementation of HeapRevolver in Linux and Windows, and report its evaluation results. The results show that HeapRevolver can prevent attacks that exploit existing UAF vulnerabilities. In addition, the overhead is small

Liver Parenchyma Perforation following Endoscopic Retrograde Cholangiopancreatography

Although endoscopic retrograde cholangiopancreatography (ERCP) is an effective modality for the diagnosis and treatment of biliary and pancreatic diseases, it is still related with several severe complications. We report on the case of a female patient who developed liver parenchyma perforation following ERCP. She underwent ERCP with sphincterotomy and extraction of a common bile duct stone. Shortly after ERCP, abdominal distension was identified. Abdominal computed tomography revealed intraabdominal air leakage and leakage of contrast dye penetrating the liver parenchyma into the space around the spleen. Since periampullary perforation related to sphincterotomy could not be denied, she was referred for immediate surgery. Obvious perforation could not be found at surgery. Cholecystectomy, insertion of a T tube into the common bile duct, placement of a duodenostomy tube and drainage of the retroperitoneum were performed. She did well postoperatively and was discharged home on postoperative day 28. In conclusion, as it is well recognized that perforation is one of the most serious complication related to ERCP, liver parenchyma perforation should be suspected as a cause

The Japanese space gravitational wave antenna; DECIGO

DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. DECIGO is expected to open a new window of observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing various mysteries of the universe such as dark energy, formation mechanism of supermassive black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of three drag-free spacecraft, whose relative displacements are measured by a differential Fabry– Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre- DECIGO first and finally DECIGO in 2024

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Mixed-mode monolithic silica as a chromatographic separation medium

Capillary electro chromatography (CEC) is a separation technique that combines the dual properties of capillary zone electrophoresis (CZE) and micro-liquid chromatography (µ-LC). A hybrid-type silica monolith capillary column was prepared from a mixture of tetramethoxysilanes (TMOS) and methyltrimethoxysilanes (MTMS). Surface modification with octadecyldimethyl-(N- N-diethylamino)silane (ODS-DEA) and N-3[-(dimethylamino)propyl]acrylamide methyl] chloride-quaternary salt, (DMAPAA-Q) was carried out to form a mixed-mode of C 18 and a strong anion exchange stationary phase. The synthesized mixed-mode silica monolithic column was then characterized physically with a scanning electron microscope (SEM) and shown to have an average through-pore size and skeleton size of 2.2 µm and 2.0 µm, respectively. This new column with mixed-mode characteristic of reversed-phase (RP) and strong anion exchange (SAX) functionalities was then applied as the stationary phase in CEC for the separation of inorganic and organic ions using a 50mM phosphate electrolyte of pH 6.9. The inorganic and organic anions were base-line separated within 10min with column efficiency up to 114 900 plates/min

Making a Robot Dance to Music Using Chaotic Itinerancy in a Network of FitzHugh-Nagumo Neurons

Abstract. We propose a technique to make a robot execute free and solitary dance movements on music, in a manner which simulates the dynamic alternations between synchronisation and autonomy typically observed in human behaviour. In contrast with previous approaches, we preprogram neither the dance patterns nor their alternation, but rather build in basic dynamics in the robot, and let the behaviour emerge in a seemingly autonomous manner. The robot motor commands are generated in real-time by converting the output of a neural network processing a sequence of pulses corresponding to the beats of the music being danced to. The spiking behaviour of individual neurons is controlled by a biologically-inspired model (FitzHugh-Nagumo). Under appropriate parameters, the network generates chaotic itinerant behaviour among low-dimensional local attractors. A robot controlled this way exhibits a variety of motion styles, some being periodic and strongly coupled to the musical rhythm and others being more independent, as well as spontaneous jumps from one style of motion to the next. The resulting behaviour is completely deterministic (as the solution of a non-linear dynamical system), adaptive to the music being played, and believed to be an interesting compromise between synchronisation and autonomy.