Biblio

While the Internet of Things (IoT) is embraced as important tools for efficiency and productivity, it is becoming an increasingly attractive target for cybercriminals. This work represents the first endeavor to develop practical Puncturable Attribute Based Encryption schemes that are light-weight and applicable in IoTs. In the proposed scheme, the attribute-based encryption is adopted for fine grained access control. The secret keys are puncturable to revoke the decryption capability for selected messages, recipients, or time periods, thus protecting selected important messages even if the current key is compromised. In contrast to conventional forward encryption, a distinguishing merit of the proposed approach is that the recipients can update their keys by themselves without key re-issuing from the key distributor. It does not require frequent communications between IoT devices and the key distribution center, neither does it need deleting components to expunge existing keys to produce a new key. Moreover, we devise a novel approach which efficiently integrates attribute-based key and punctured keys such that the key size is roughly the same as that of the original attribute-based encryption. We prove the correctness of the proposed scheme and its security under the Decisional Bilinear Diffie-Hellman (DBDH) assumption. We also implement the proposed scheme on Raspberry Pi and observe that the computation efficiency of the proposed approach is comparable to the original attribute-based encryption. Both encryption and decryption can be completed within tens of milliseconds.

Medical organizations find it challenging to adopt cloud-based electronic medical records services, due to the risk of data breaches and the resulting compromise of patient data. Existing authorization models follow a patient centric approach for EHR management where the responsibility of authorizing data access is handled at the patients' end. This however creates a significant overhead for the patient who has to authorize every access of their health record. This is not practical given the multiple personnel involved in providing care and that at times the patient may not be in a state to provide this authorization. Hence there is a need of developing a proper authorization delegation mechanism for safe, secure and easy cloud-based EHR management. We have developed a novel, centralized, attribute based authorization mechanism that uses Attribute Based Encryption (ABE) and allows for delegated secure access of patient records. This mechanism transfers the service management overhead from the patient to the medical organization and allows easy delegation of cloud-based EHR's access authority to the medical providers. In this paper, we describe this novel ABE approach as well as the prototype system that we have created to illustrate it.

In recent years, many users have uploaded data to the cloud for easy storage and sharing with other users. At the same time, security and privacy concerns for the data are growing. Attribute-based encryption (ABE) enables both data security and access control by defining users with attributes so that only those users who have matching attributes can decrypt them. For real-world applications of ABE, revocation of users or their attributes is necessary so that revoked users can no longer decrypt the data. In actual implementations, ABE is used in hybrid with a symmetric encryption scheme such as the advanced encryption standard (AES) where data is encrypted with AES and the AES key is encrypted with ABE. The hybrid encryption scheme requires re-encryption of the data upon revocation to ensure that the revoked users can no longer decrypt that data. To re-encrypt the data, the data owner (DO) must download the data from the cloud, then decrypt, encrypt, and upload the data back to the cloud, resulting in both huge communication costs and computational burden on the DO depending on the size of the data to be re-encrypted. In this paper, we propose an attribute-based proxy re-encryption method in which data can be re-encrypted in the cloud without downloading any data by adopting both ABE and Syalim's encryption scheme. Our proposed scheme reduces the communication cost between the DO and cloud storage. Experimental results show that the proposed method reduces the communication cost by as much as one quarter compared to that of the trivial solution.

Most centralized systems allow data access to its cloud user if a cloud user has a certain set of satisfying attributes. Presently, one method to compete such policies is to use an authorized cloud server to maintain the user data and have access control over it. At times, when one of the servers keeping data is compromised, the security of the user data is compromised. For getting access control, maintaining data security and obtaining precise computing results, the data owners have to keep attribute-based security to encrypt the stored data. During the delegation of data on cloud, the cloud servers may be tampered by the counterfeit cipher-text. Furthermore, the authorized users may be cheated by retorting them that they are unauthorized. Largely the encryption control access attribute policies are complex. In this paper, we present Cipher-text Policy Attribute-Based Encryption for maintaining complex access control over encrypted data with verifiable customizable authorization. The proposed technique provides data confidentiality to the encrypted data even if the storage server is comprised. Moreover, our method is highly secured against collusion attacks. In advance, performance evaluation of the proposed system is elaborated with implementation of the same.

In blockchain-based systems, malicious behaviour can be detected using auditable information in transactions managed by distributed ledgers. Besides cryptocurrency, blockchain technology has recently been used for other applications, such as file storage. However, most of existing blockchain- based file storage systems can not revoke a user efficiently when multiple users have access to the same file that is encrypted. Actually, they need to update file encryption keys and distribute new keys to remaining users, which significantly increases computation and bandwidth overheads. In this work, we propose a blockchain and proxy re-encryption based design for encrypted file sharing that brings a distributed access control and data management. By combining blockchain with proxy re-encryption, our approach not only ensures confidentiality and integrity of files, but also provides a scalable key management mechanism for file sharing among multiple users. Moreover, by storing encrypted files and related keys in a distributed way, our method can resist collusion attacks between revoked users and distributed proxies.

Ubiquitous Healthcare System (U-Healthcare) is a well-known application of wireless sensor networking (WSN). In this system, the sensors take less power for operating the function. As the data transfers between sensor and other stations is sensitive so there needs to provide a security scheme. Due to the low life of sensor nodes in Wireless Sensor Networks (WSN), asymmetric key based security (AKS) architecture is always considered as unsuitable for these types of networks. Several papers have been published in recent past years regarding how to incorporate AKS in WSN, Haque et al's Asymmetric key based Architecture (AKA) is one of them. But later it is found that this system has authentication problem and therefore prone to man-in-the-middle (MITM) attack, furthermore it is not a truly asymmetric based scheme. We address these issues in this paper and proposed a complete asymmetric approach using PEKS-PM (proposed by Pham in [8]) to remove impersonation attack. We also found some other vulnerabilities in the original AKA system and proposed solutions, therefore making it a better and enhanced asymmetric key based architecture.

The use of real-time video streaming is increasing day-by-day, and its security has become a serious issue now. Video encryption is a challenging task because of its large frame size. Video encryption can be done with symmetric key as well as asymmetric key encryption. Among different asymmetric key encryption technique, ECC performs better than other algorithms like RSA in terms of smaller key size and faster encryption and decryption operation. In this work, we have analyzed the performance of 18 different ECC curves and suggested some suitable curves for real-time video encryption.

Cryptography is a widespread technique that maintains information security over insecure networks. The symmetric encryption scheme provides a good security, but the key exchange is difficult on the other hand, in the asymmetric encryption scheme, key management is easier, but it does not offer the same degree of security compared to symmetric scheme. A hybrid cryptosystem merges the easiness of the asymmetric schemes key distribution and the high security of symmetric schemes. In the proposed hybrid cryptosystem, Serpent algorithm is used as a data encapsulation scheme and Elliptic Curve Cryptography (ECC) is used as a key encapsulation scheme to achieve key generation and distribution within an insecure channel. This modification is done to tackle the issue of key management for Serpent algorithm, so it can be securely used in multimedia protection.

Public key cryptography or asymmetric keys are widely used in the implementation of data security on information and communication systems. The RSA algorithm (Rivest, Shamir, and Adleman) is one of the most popular and widely used public key cryptography because of its less complexity. RSA has two main functions namely the process of encryption and decryption process. Digital Signature Algorithm (DSA) is a digital signature algorithm that serves as the standard of Digital Signature Standard (DSS). DSA is also included in the public key cryptography system. DSA has two main functions of creating digital signatures and checking the validity of digital signatures. In this paper, the authors compare the computational times of RSA and DSA with some bits and choose which bits are better used. Then combine both RSA and DSA algorithms to improve data security. From the simulation results, the authors chose RSA 1024 for the encryption process and added digital signatures using DSA 512, so the messages sent are not only encrypted but also have digital signatures for the data authentication process.

In this work NTRU-like cryptosystem NTRU Prime IIT Ukraine, which is created on the basis of existing cryptographic transformations end-to-end encryption type, is considered. The description of this cryptosystem is given and its analysis is carried out. Also, features of its implementation, comparison of the main characteristics and indicators, as well as the definition of differences from existing NTRU-like cryptographic algorithms are presented. Conclusions are made and recommendations are given.

Anonymity networks provide privacy to the users by relaying their data to multiple destinations in order to reach the final destination anonymously. Multilayer of encryption is used to protect the users' privacy from attacks or even from the operators of the stations. In this research, we showed how flow analysis could be used to identify encrypted anonymity network traffic under four scenarios: (i) Identifying anonymity networks compared to normal background traffic; (ii) Identifying the type of applications used on the anonymity networks; (iii) Identifying traffic flow behaviors of the anonymity network users; and (iv) Identifying / profiling the users on an anonymity network based on the traffic flow behavior. In order to study these, we employ a machine learning based flow analysis approach and explore how far we can push such an approach.

We introduce MobiCeal, the first practical Plausibly Deniable Encryption (PDE) system for mobile devices that can defend against strong coercive multi-snapshot adversaries, who may examine the storage medium of a user's mobile device at different points of time and force the user to decrypt data. MobiCeal relies on "dummy write" to obfuscate the differences between multiple snapshots of storage medium due to existence of hidden data. By incorporating PDE in block layer, MobiCeal supports a broad deployment of any block-based file systems on mobile devices. More importantly, MobiCeal is secure against side channel attacks which pose a serious threat to existing PDE schemes. A proof of concept implementation of MobiCeal is provided on an LG Nexus 4 Android phone using Android 4.2.2. It is shown that the performance of MobiCeal is significantly better than prior PDE systems against multi-snapshot adversaries.

Most mobile applications generate local data on internal memory with SharedPreference interface of an Android operating system. Therefore, many possible loopholes can access the confidential information such as passwords. We propose a hybrid encryption approach for SharedPreferences to protect the leaking confidential information through the source code. We develop an Android application and store some data using SharedPreference. We produce different experiments with which this data could be accessed. We apply Hybrid encryption approach combining encryption approach with Android Keystore system, for providing better encryption algorithm to hide sensitive data.

Vehicular Ad-hoc Networks (VANETs) are a subset of Mobile Ad-hoc Networks (MANETs). They are deployed to introduce the ability of inter-communication among vehicles in order to guarantee safety and provide services for people while driving. VANETs are exposed to many types of attacks like denial of service, spoofing, ID disclosure and Sybil attacks. In this paper, a novel lightweight approach for preventing Sybil attack in VANETs is proposed. The presented protocol scheme uses symmetric key encryption and authentication between Road Side Units (RSUs) and vehicles on the road so that no malicious vehicle could gain more than one identity inside the network. This protocol does not need managers for Road Side Units (RSUs) or Certification Authority (CA) and uses minimum amount of messages exchanged with RSU making the scheme efficient and effective.

A mobile ad hoc network (MANET) is vulnerable to many types of attacks. Thus, security has turned out to be an important factor to facilitate secured communication between mobile nodes in a wireless environment. In this paper we propose a new approach to provide reliable and secure data transmission in MANETs under possible blackhole attacks based on ad hoc on-demand multipath distance vector (AOMDV) protocol and homomorphic encryption scheme for security. The performance of the proposed scheme is stable but that of AOMDV is found to be degrading with the intrusion of malicious nodes in the network. Simulation results show the improvement of packet delivery ratio and network throughput in the presence of blackhole nodes in our proposed scheme.

The recently applied General Data Protection Regulation (GDPR) aims to protect all EU citizens from privacy and data breaches in an increasingly data-driven world. Consequently, this deeply affects the factory domain and its human-centric automation paradigm. Especially collaboration of human and machines as well as individual support are enabled and enhanced by processing audio and video data, e.g. by using algorithms which re-identify humans or analyse human behaviour. We introduce most significant impacts of the recent legal regulation change towards the automations domain at a glance. Furthermore, we introduce a representative scenario from production, deduce its legal affections from GDPR resulting in a privacy-aware software architecture. This architecture covers modern virtualization techniques along with authorization and end-to-end encryption to ensure a secure communication between distributes services and databases for distinct purposes.

Recent worldwide cybersecurity attacks caused by Cryptographic Ransomware infected systems across countries and organizations with millions of dollars lost in paying extortion amounts. This form of malicious software takes user files hostage by encrypting them and demands a large ransom payment for providing the decryption key. Signature-based methods employed by Antivirus Software are insufficient to evade Ransomware attacks due to code obfuscation techniques and creation of new polymorphic variants everyday. Generic Malware Attack vectors are also not robust enough for detection as they do not completely track the specific behavioral patterns shown by Cryptographic Ransomware families. This work based on analysis of an extensive dataset of Ran-somware families presents RansomWall, a layered defense system for protection against Cryptographic Ransomware. It follows a Hybrid approach of combined Static and Dynamic analysis to generate a novel compact set of features that characterizes the Ransomware behavior. Presence of a Strong Trap Layer helps in early detection. It uses Machine Learning for unearthing zero-day intrusions. When initial layers of RansomWall tag a process for suspicious Ransomware behavior, files modified by the process are backed up for preserving user data until it is classified as Ransomware or Benign. We implemented RansomWall for Microsoft Windows operating system (the most attacked OS by Cryptographic Ransomware) and evaluated it against 574 samples from 12 Cryptographic Ransomware families in real-world user environments. The testing of RansomWall with various Machine Learning algorithms evaluated to 98.25% detection rate and near-zero false positives with Gradient Tree Boosting Algorithm. It also successfully detected 30 zero-day intrusion samples (having less than 10% detection rate with 60 Security Engines linked to VirusTotal).

Microsoft BitLocker full-disk encryption has been widely implemented at Lehigh University since 2014 on both laptop and desktop computers. This retrospective review will summarize BitLocker's selection factors, initial testing, mass deployment, and important lessons learned. Additionally, this review will also discuss the university's transition to Windows 10 and how it positively impacted the use of BitLocker.

Because major smartphone platforms are equipped with Bluetooth Low Energy (BLE) capabilities, more and more smart devices have adopted BLE technologies to communicate with smartphones. In order to support the mesh topology in BLE networks, several proposals have been designed. Among them, the Bluetooth Special Interest Group (SIG) recently released a specification for Bluetooth mesh networks based upon BLE technology. This paper focuses on this standard solution and analyses its security protocol with hardware security in mind. As it is expected that internet of things (IoT) devices will be deployed everywhere, the risk of physical attacks must be assessed. First, we provide a comprehensive survey of the security features involved in Bluetooth mesh. Then, we introduce some physical attacks identified as serious threats for the IoT and discuss their relevance in the case of Bluetooth mesh networks. Finally, we briefly discuss possible countermeasures to reach a secure implementation.

Parameter estimation in wireless sensor networks (WSN) using encrypted non-binary quantized data is studied. In a WSN, sensors transmit their observations to a fusion center through a wireless medium where the observations are susceptible to unauthorized eavesdropping. Encryption approaches for WSNs with fixed threshold binary quantization were previously explored. However, fixed threshold binary quantization limits parameter estimation to scalar parameters. In this paper, we propose a stochastic encryption approach for WSNs that can operate on non-binary quantized observations and has the capability for vector parameter estimation. We extend a binary stochastic encryption approach proposed previously, to a non-binary generalized case. Sensor outputs are quantized using a quantizer with R + 1 levels, where R $ε$ 1, 2, 3,..., encrypted by flipping them with certain flipping probabilities, and then transmitted. Optimal estimators using maximum-likelihood estimation are derived for both a legitimate fusion center (LFC) and a third party fusion center (TPFC) perspectives. We assume the TPFC is unaware of the encryption. Asymptotic analysis of the estimators is performed by deriving the Cramer-Rao lower bound for LFC estimation, and the asymptotic bias and variance for TPFC estimation. Numerical results validating the asymptotic analysis are presented.

Audit logs are widely used in information systems nowadays. In cloud computing and cloud storage environment, audit logs are required to be encrypted and outsourced on remote servers to protect the confidentiality of data and the privacy of users. The searchable encrypted audit logs support a search on the encrypted audit logs. In this paper, we propose a privacy-preserving and unforgeable searchable encrypted audit log scheme based on PEKS. Only the trusted data owner can generate encrypted audit logs containing access permissions for users. The semi-honest server verifies the audit logs in a searchable encryption way before granting the operation rights to users and storing the audit logs. The data owner can perform a fine-grained conjunctive query on the stored audit logs, and accept only the valid audit logs. The scheme is immune to the collusion tamper or fabrication conducted by server and user. Concrete implementations of the scheme is put forward in detail. The correct of the scheme is proved, and the security properties, such as privacy-preserving, searchability, verifiability and unforgeability are analyzed. Further evaluation of computation load shows that the design is of considerable efficiency.

As one of the most commonly used protocols in VPN technology, IPsec has many advantages. However, certain difficulties are posed to the audit work by the protection of in-formation. In this paper, we propose an audit method via man-in-the-middle mechanism, and design a prototype system with DPDK technology. Experiments are implemented in an IPv4 network environment, using default configuration of IPsec VPN configured with known PSK, on operating systems such as windows 7, windows 10, Android and iOS. Experimental results show that the prototype system can obtain the effect of content auditing well without affecting the normal communication between IPsec VPN users.

In a Semi-autonomic cloud auditing architecture we weaved in privacy enhancing mechanisms [15] by applying the public key version of the Somewhat homomorphic encryption (SHE) scheme from [4]. It turns out that the performance of the SHE can be significantly improved by carefully deriving relevant crypto parameters from the concrete cloud auditing use cases for which the scheme serves as a privacy enhancing approach. We provide a generic algorithm for finding good SHE parameters with respect to a given use case scenario by analyzing and taking into consideration security, correctness and performance of the scheme. Also, to show the relevance of our proposed algorithms we apply it to two predominant cloud auditing use cases.

With all data services of cloud, it's not only stored the data, although shared the data among the multiple users or clients, which make doubt in its integrity due to the existence of software/hardware error along with human error too. There is an existence of several mechanisms to allow data holders and public verifiers to precisely, efficiently and effectively audit integrity of cloud data without accessing the whole data from server. After all, public auditing on the integrity of shared data with pervious extant mechanisms will somehow affirm the confidential information and its identity privacy to the public verifiers. In this paper, to achieve the privacy preserving public for auditing, we intended an explanation for TPA using three way handshaking protocol through the Extensible Authentication Protocol (EAP) with liberated encryption standard. Appropriately, from the cloud, we use the VerifyProof execute by TPA to audit to certify. In addition to this mechanism, the identity of each segment in the shared data is kept private from the public verifiers. Moreover, rather than verifying the auditing task one by one, this will capable to perform, the various auditing tasks simultaneously.

The importance of Networked Control Systems (NCS) is steadily increasing due to recent trends such as smart factories. Correct functionality of such NCS needs to be protected as malfunctioning systems could have severe consequences for the controlled process or even threaten human lives. However, with the increase in NCS, also attacks targeting these systems are becoming more frequent. To mitigate attacks that utilize captured sensor data in an NCS, transferred data needs to be protected. While using well-known methods such as Transport Layer Security (TLS) might be suitable to protect the data, resource constraint devices such as sensors often are not powerful enough to perform the necessary cryptographic operations. Also, as we will show in this paper, applying simple encryption in an NCS may enable easy Denial-of-Service (DoS) attacks by attacking single bits of the encrypted data. Therefore, in this paper, we present a hardware-based approach that enables sensors to perform the necessary encryption while being robust against (injected) bit failures.