This book constitutes the proceedings of the 22nd International Workshop on Security and Trust Management, STM 2026 held in Rome, Italy during September 14–18, 2026, Proceedings.

The total of 15 full papers included in the proceedings was carefully reviewed and selected from 39 submissions.They were organized in topical sections as follows: Access Control, Identity and Privacy Guarantees; Network Security and Cyber-Physical Systems; Software Security and Vulnerability Analysis; and Cryptographic Protocols and Verifiability.