INTRODUCTION Misuse of opioid analgesics, in combination with diversion, dependence, and fatal overdoses, presents a serious problem for public health, which affects many countries worldwide. Within this context, tampering with opioids has been associated with serious harm. The aim of the present study was to assess the tampering potential of codeine combination analgesics on the market (contai...

A non-malleable code protects messages against various classes of tampering. Informally, a code is non-malleable if the effect of applying any tampering function on an encoded message is to either retain the message or to replace it with an unrelated message. Two main challenges in this area – apart from establishing the feasibility against different families of tampering – are to obtain explic...

Unauthorized tampering in speech signals has brought serious problems when verifying the originality and integrity of speech signals. Digital watermarking can effectively check if the original signals have been tampered by embedding digital data into them. This paper proposes a tampering detection scheme for speech signals based on formant enhancement-based watermarking. Watermarks are embedded...

Digital images are powerful and widely used communication medium in many fields like medical imaging, digital forensics, surveillance, journalism, etc. The availability of sophisticated digital image technology has given rise to image forgery. The forgeries are very difficult for a human eye to detect. Passive tampering detection method aims to detect the tampering areas in the digital images w...

In this dissertation we investigate the question of protecting cryptographic devices from tampering attacks. Traditional theoretical analysis of cryptographic devices is based on black-box models which do not take into account the attacks on the implementations, known as physical attacks. In practice such attacks can be executed easily, e.g. by heating the device, as substantiated by numerous w...

A non-malleable code protects messages against a class of tampering functions. Informally, a code is non-malleable if the effect of applying any tampering function on an encoded message is to either retain the message or to replace it with an unrelated message. Two main challenges in this area – apart from establishing the feasibility against different families of tampering – are to obtain expl...

We revisit the question of constructing public-key encryption and signature schemes with security in the presence of bounded leakage and tampering memory attacks. For signatures we obtain the first construction in the standard model; for public-key encryption we obtain the first construction free of pairing (avoiding non-interactive zero-knowledge proofs). Our constructions are based on generic...

The notion of non-malleable codes was introduced as a relaxation of standard error-correction and error-detection. Informally, a code is non-malleable if the message contained in a modified codeword is either the original message, or a completely unrelated value. In the information theoretic setting, although existence of such codes for various rich classes of tampering functions is known, expl...