This two-volume set LNICST 704 - 705 constitutes the proceedings of the 22nd EAI International Conference on Security and Privacy in Communication Networks, SecureComm 2026, held in Lancaster, UK, during July 21–24, 2026. The 50 full papers and 1 poster paper included in these volumes were carefully reviewed and selected from 143 submissions. They are organized in the following topical sections: Part I: Authentication, Biometrics & Human Factors; Mobile/Network Security & Measurement; Cryptanalysis, Post-Quantum & Smart-Contract Incentives; Secure & Privacy-Preserving Federated Learning; Blockchain Protocols, Mining & Cross-Chain Systems; Cryptography: Credentials, FE, FHE &  PIR; Post-Quantum & Lattice Cryptography; and Applied Crypto for Authentication & Data Hiding. Part II: AI for Threat Detection & Network Defense; Network Measurement, Fingerprinting & Routing Anomalies; System & Software Security; LLMs and LLM-assisted Analysis; Privacy-Preserving Analytics & Energy Trading; Work-in-Progress session; and Posters.