Session is an open-source, public-key-based secure messaging application which uses a set of decentralised storage servers and an onion routing protocol to send end-to-end encrypted messages with minimal exposure of user metadata. It does this while providing the common features expected of mainstream messaging applications, such as multi-device syncing, offline inboxes, and voice/video calling.
APT traffic detection is an important task in network security domain, which is of great significance in the field of enterprise security. Most APT traffic uses encrypted communication protocol as data transmission medium, which greatly increases the difficulty of detection. This paper analyzes the existing problems of current APT encrypted traffic detection methods based on machine learning, and proposes an APT encrypted traffic detection method based on two parties and multi-session. This method only needs to extract a small amount of features, such as session sequence, session time interval…
Most encrypted data formats leak metadata via their plaintext headers, such as format version, encryption schemes used, number of recipients who can decrypt the data, and even the recipients' identities. This leakage can pose security and privacy risks to users, e.g., by revealing the full membership of a group of collaborators from a single encrypted e-mail, or by enabling an eavesdropper to fingerprint the precise encryption software version and configuration the sender used. We propose that future encrypted data formats improve security and privacy hygiene by producing $\textit{Padded Unifo…
In this paper, a multilayer perceptron guided key generation for encryption/decryption (MLPKG) has been proposed through recursive replacement using mutated character code generation for wireless communication of data/information. Multilayer perceptron transmitting systems at both ends accept an identical input vector, generate an output bit and the network are trained based on the output bit which is used to form a protected variable length secret-key. For each session, different hidden layer of multilayer neural network is selected randomly and weights or hidden units of this selected hidden…
Secure communications are playing increasing roles in society, particularly in finance, journalism, and military projects. Current methods of securing e-mail and similar messaging methods rely on encryption of the message body, but the header with addressing information remains plaintext. This allows third party eavesdroppers to collect and analyse the header metadata and construct a network model of the participants in conversations (who, where, when, subject). In this article, we describe a method of communication where the header is also encrypted, hindering the assembly of the communicatio…
The technique considers a message as binary string on which a Efficient Cryptographic Protocol using Recursive Bitwise amd pairs of Bits of operation (RBPBO) is performed. A block of n bits is taken as an input stream, where n varies from 4 to 256, from a continuous stream of bits and the technique operates on it to generate the intermediate encrypted stream. This technique directly involves all the bits of blocks in a boolean operation and a session key. The same operation is performed repeatedly for different block sizes as per the specification of a session key to generate the final encrypt…
Emerging Non-Volatile Memories (NVMs) are promising contenders for building future memory systems. On the other side, unlike DRAM systems, NVMs can retain data even after power loss and thus enlarge the attack surface. While data encryption and integrity verification have been proposed earlier for DRAM systems, protecting and recovering secure memories becomes more challenging with persistent memory. Specifically, security metadata, e.g., encryption counters and Merkle Tree data, should be securely persisted and recovered across system reboots and during recovery from crashes. Not persisting u…
In this paper, we propose a session based bit level symmetric key cryptographic technique and it is termed as Spiral Matrix Based Bit Orientation Technique (SMBBOT). SMBBOT consider the input plain text as binary bit stream. During encryption this stream is chopped into manageable sized blocks with variable lengths. Bits of these blocks are taken from MSB to LSB to fit into a square matrix of suitable order following the concept of Spiral matrix. This square matrix splits into 2x2 sub-matrices. Bits are taken column-wise from all 2x2 sub-matrices to form the encrypted binary string. Cipher tex…
Even as end-to-end encrypted communication becomes more popular, private messaging remains a challenging problem due to metadata leakages, such as who is communicating with whom. Most existing systems that hide communication metadata either (1) do not scale easily, (2) incur significant overheads, or (3) provide weaker guarantees than cryptographic privacy, such as differential privacy or heuristic privacy. This paper presents XRD (short for Crossroads), a metadata private messaging system that provides cryptographic privacy, while scaling easily to support more users by adding more servers. A…
- In this paper a session based symmetric key encryption system has been proposed and is termed as Permutated Cipher Technique (PCT). This technique is more fast, suitable and secure for larger files. In this technique the input file is broken down into blocks of various sizes (of 2 power n order) and encrypted by shifting the position of each bit by a certain value for a certain number of times. A key is generated randomly wherein the length of each block is determined. Each block length generates a unique value of number of bits to be skipped. This value determines the new position of the bi…
Encrypted deduplication combines encryption and deduplication to simultaneously achieve both data security and storage efficiency. State-of-the-art encrypted deduplication systems mainly build on deterministic encryption to preserve deduplication effectiveness. However, such deterministic encryption reveals the underlying frequency distribution of the original plaintext chunks. This allows an adversary to launch frequency analysis against the ciphertext chunks and infer the content of the original plaintext chunks. In this paper, we study how frequency analysis affects information leakage in e…
This document is a technical overview and discussion of our work, a protocol for secure group messaging. By secure we mean for the actual users i.e. end-to-end security, as opposed to "secure" for irrelevant third parties. Our work provides everything needed to run a messaging session between real users on top of a real transport protocol. That is, we specify not just a key exchange, but when and how to run these relative to transport-layer events; how to achieve liveness properties such as reliability and consistency, that are time-sensitive and lie outside of the send-receive logic that cryp…
Emerging Non-Volatile Memories (NVMs) bring a unique challenge to the security community, namely persistent security. As NVM-based memories are expected to restore their data after recovery, the security metadata must be recovered as well. However, persisting all affected security metadata on each memory write would significantly degrade performance and exacerbate the write endurance problem. Moreover, recovery time can increase significantly (up to hours for practical memory sizes) when security metadata are not updated strictly. Counter trees are used in state-of-the-art commercial secure pr…
Criminals are increasingly using mobile based communication applications, like WhatsApp, that have end-to-end encryption to connect to each other. This makes traditional analysis of call graphs, or traffic analysis, virtually impossible and so is a hindrance for law enforcement personnel. Old methods of traffic analysis have been rendered useless and criminals, including arms dealers and terrorists, are able to engage in criminal activity undetected by police. At present, law enforcement must use extensive manual effort to parse data provided by cell companies to extract information. We have b…
Many widely used Internet messaging and calling apps, such as WhatsApp, Viber, Telegram, and Signal, have deployed an end-to-end encryption functionality. To defeat potential MITM attackers against the key exchange protocol, the approach relies on users to perform a code verification task whereby each user must compare the code (a fingerprint of the cryptographic keys) computed by her app with the one computed by the other user's app and reject the session if the two do not match. In this paper, we study the security and usability of this human-centered code verification task for a setting whe…
Multi-View Fusion for Encrypted C2 Detection: A Leakage-Controlled Measurement Study of Evaluation Pitfalls
Academy of Cryptography Techniques（密码技术学院）；Ho Chi Minh City University of Technology (HCMUT)（胡志明市理工大学）；Vietnam National University Ho Chi Minh City（越南胡志明市国家大学）
