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Cryptography Threats
Published in Nicholas Kolokotronis, Stavros Shiaeles, Cyber-Security Threats, Actors, and Dynamic Mitigation, 2021
Konstantinos Limniotis, Nicholas Kolokotronis
Usage of weak hash functions in constructing MACs and/or signing the messages is also an important source of threat. The cryptographic community is aware that MD5 and SHA-1 are non-collision resistant hash functions any more (since 2005 and 2017, respectively). However, the use of MD5 and SHA-1 is mandated by the TLS 1.0-1.1 specifications, whereas they constitute an option in TLS 1.2. In 2016, researchers presented an attack (actually, a family of attacks) being called SLOTH (Security Losses from Obsolete and Truncated Transcript Hashes) [31]18, which allows the attacker, due to the aforementioned non-collision resistance, to modify the Hello messages in the handshake without being detected (in a MiTM approach); this is achieved by creating a prefix-collision in the transcript hashes. This attack is feasible in TLS 1.2.
Denaturing the Internet Through a Trust Appraisement Paradigm by QoS Accretion
Published in Gulshan Shrivastava, Sheng-Lung Peng, Himani Bansal, Kavita Sharma, Meenakshi Sharma, New Age Analytics, 2020
Key Generation Using Hash Function: It uses hash function to generate the keys and the cluster head distributes the keys after calculating the trust values of the hubs. A hub must have the key for receiving the packet. The key generation approach utilizes the message digest algorithm (MD5) hash algorithm for generating unique keys. MD5 is the cryptographic hash function which accepts input as message of arbitrary length and generates fixed length message digest value. The output is a 128-bit digest value. The outputs created are unique for each input and it is computationally infeasible to generate two messages with the same message digest as depicted in Figure 7.5.
A Novel LC-DEH Algorithm to Enhance Efficiency and Security for Reliable Data Transmission in Blockchain with IoT-Based Healthcare Systems
Published in Ambikapathy, R. Shobana, Logavani, Dharmasa, Reinvention of Health Applications with IoT, 2022
G. Uganya, Radhika Baskar, M. Balasaraswathi, N. Vijayaraj, D. Rajalakshmi
Message Digest 5: MD5 is one of the cryptography hash algorithms that produce the 128-bit output hash. It can be expressed as a 32-digit hexadecimal number to secure the files. It has four rounds and 64 steps to produce the hash value. It provides secure communication due to its irreversible property. It is impossible to make the two messages with the same hash value. In this function, every step result will be added to the previous step. The secure hash algorithm is classified into three families.
Analyzing execution path non-determinism of the Linux kernel in different scenarios
Published in Connection Science, 2023
Yucong Chen, Xianzhi Tang, Shuaixin Xu, Fangfang Zhu, Qingguo Zhou, Tien-Hsiung Weng
The MD5 algorithm is a widely used hash function that accepts any length message as an input and transforms it into a fixed length (128 bits) output known as a hash value (Rivest, 1992). The MD5 algorithm was initially designed to encrypt hash functions, but it was later proved flawed and decipherable; thus, it is no longer suitable for security authentication (Black et al., 2006; Lenstra et al., 2005). Nevertheless, the MD5 algorithm can still be used to check and verify data integrity (de Guzman et al., 2019; Sandeep & Abdulhayan, 2020), but it can only prevent accidental data corruption. As seen in Figure 2, in our study, the function execution paths of the system calls were used as the input of the MD5 algorithm, and the generated 128-bit byte sequences as the unique identifier of the execution paths of the system call (Allende, 2022; Allende, Mc Guire, Perez, Monsalve, & Obermaisser, 2021), as shown in Figure 2. This identifier can subsequently be used to analyse the diversity of system call function execution paths.
SEEDDUP: A Three-Tier SEcurE Data DedUPlication Architecture-Based Storage and Retrieval for Cross-Domains Over Cloud
Published in IETE Journal of Research, 2023
In [23] authors have proposed AR-Dedupe (Application-aware) for the cluster deduplication system. It obtained low communication overhead and high data deduplication rate via routing server. This result, due to selecting handprints, finds super-chunks based on similarity. Furthermore, the routing server chooses the best (optimal) deduplication server node, which is only used for communicating to the routing server. Finally, index is created based on application types, which have little improvement for increasing rate data deduplication. AR-Dedupe is a time-consuming process which does not handle much data owners request at a time. Xiong et al. [24] have proposed RSE-PoW (Role Symmetric Encryption with Proof of Ownership) for secure deduplication. The proposed scheme uses symmetric encryption, bloom filter, and proof of ownership. After key generation, cloud server verifies the hash. If two results are the same, CS does not store the file. If they are not the same, hash of block is encrypted and stored in CS. The RSE-PoW protocol resists only against side-channel attacks, but brute force attackers may largely involve in this system by the use of wrong keys and passwords. In [25] RMD (resemblance and mergence-based deduplication) is proposed, which leverages indexing and bloom filter array. Data resemblance algorithm is concentrated, which identifies and clusters segments of resemblance for data and puts resemblance segments in the same bin. In order to find duplicate data, it finds only the bin which contains same data. This process is speedup the querying process by mergence strategy. When segment clustering is not accurate, it results in poor performance and increased RAM requirements. In [26] various file deduplication schemes are based on different characteristics, such as file name, file size, and partial or full content of hash value. Experiment results show that CPU usage is reduced by 25% for partial MD5 scheme and 19.3% is reduced for full MD5 scheme. MD5 is faster than other hashing algorithms, but not secure than SHA family. The proposed scheme is slight worse in data sharing, searching, and management services.