This book constitutes the refereed proceedings of the 21th International Conference on Information and Communications Security, ICICS 2019, held in Beijing, China, in December 2019. The 47 revised full papers were carefully selected from 199 submissions. The papers are organized in topics on malware analysis and detection, IoT and CPS security enterprise network security, software security, system security, authentication, applied cryptograph internet security, machine learning security, machine learning privacy, Web security, steganography and steganalysis.

Table of Contents:
Prototype-based malware trafic classification with novelty detection.- Evading API Call Sequence Based Malware Classifiers.- UBER: Combating Sandbox Evasion via User Behavior Emulators.- AADS: A Noise-Robust Anomaly Detection Framework for Industrial Control Systems.- Maged Abdelaty, Roberto Doriguzzi-Corin and Domenico Siracusa Characterizing Internet-scale ICS Automated Attacks through Long-term Honeypot Data.- Cloning Vulnerability Detection in Driver Layer of IoT Devices.- Impact of Multiple Re ections on Secrecy Capacity of Indoor VLC System.- Road Context-aware Intrusion Detection System for Autonomous Cars.- Enterprise Network Security.- Automated Cyber Threat Intelligence Reports Classification for Early Warning of Cyber Attacks in Next Generation SOC.- HeteroUI:A Framework Based on Heterogeneous Information Network Embedding for User Identification in Enterprise Networks.- CTLMD: Continuous-Temporal Lateral Movement Detection Using Graph Embedding.- VulHunter: An Automated Vulnerability Detection System based on Deep Learning and Bytecode.- Deep Learning-Based Vulnerable Function Detection: A Benchmark.- Automatic Demirci-Sel cuk Meet-in-the-Middle Attack on SKINNY with Key-bridging.- SecFlush: A Hardware/Software Collaborative Design for Real-Time Detection and Defense against Flush-Based Cache Attacks.- CDAE: Towards Empowering Denoising in Side-Channel Analysis.- Practical Evaluation Methodology of Higher-order Maskings at Different Operating Frequencies.- Privacy-Preserving eID Derivation for Self-Sovereign Identity Systems.- Provably Secure Group Authentication in the Asynchronous Communication Model.- AGE: Authentication Graph Embedding for Detecting Anomalous Login Activities.- A Multi-group Signature Scheme from Lattices.- Ciphertext Policy Attribute-Based Encryption for Circuits from LWE Assumption.- Using Equivalent Class to Solve Interval Discrete Logarithm Problem.- Parallel Steepest Ascent Hill-Climbing for High Nonlinear Boolean and VectorialBoolean Functions (S-Boxes).- Accelerating SM2 Digital Signature Algorithm using Modern Processor Features.- Improved Di erential Attacks on GIFT-64.- Adaptively Secure Puncturable Pseudorandom Functions via Puncturable Identity-Based KEMs.- Context-aware IPv6 Address Hopping.- Towards Homograph-confusable Domain Name Detection using Dual-channel CNN.- FraudJudger: Fraud Detection on Digital Payment Platforms with Fewer Labels.- CloudCoT: A Blockchain-based Cloud Service Dependency Attestation Framework.- An Adversarial Attack Based on Multi-Objective Optimization in the Neuron Selecting: Defending against Adversarial Examples in Deep Neural Networks.- Capturing the Persistence of Facial Expression Features for Deepfake.- Video Detection.- Differentially Private Frequent Itemset Mining against Incremental Updates.- Privacy-Preservinig Distributed Machine Learning based on Secret Sharing.- Privacy-preserving Decentralised Singular Value Decomposition.- WSLD: Detecting Unknown Webshell Using Fuzzy Matching and Deep Learning.- A Character-Level BiGRU-Attention For Phishing Classification.- Tear O Your Disguise: Phishing Website Detection using Visual and Network Identities.- Steganography and Steganalysis.- Hierarchical Repesentation Network for Steganalysis of QIM Steganography in Low-Bit-Rate Speech Signals.- Convolutional Neural Network based Side-Channel Attacks with Customized Filters.- DLchain: a Covert Channel over Blockchain based on Dynamic Labels.