This book constitutes the refereed proceedings of the Third International Conference on Provable Security, ProvSec 2009, held in Guangzhou, China, November 11-13, 2009. The papers are organized in topical sections on encryption, digital signature, cryptographic protocols and reduction and privacy.

Invited Talks.- A Brief History of Security Models for Confidentiality.- Symbolic Methods for Provable Security.- Encryption.- Efficient Non-interactive Universally Composable String-Commitment Schemes.- Spatial Encryption under Simpler Assumption.- Chosen-Ciphertext Secure RSA-Type Cryptosystems.- Anonymous Conditional Proxy Re-encryption without Random Oracle.- Breaking and Fixing of an Identity Based Multi-Signcryption Scheme.- Digital Signatures.- Identity-Based Verifiably Encrypted Signatures without Random Oracles.- How to Prove Security of a Signature with a Tighter Security Reduction.- Twin Signature Schemes, Revisited.- On the Insecurity of the Fiat-Shamir Signatures with Iterative Hash Functions.- Is the Notion of Divisible On-Line/Off-Line Signatures Stronger than On-Line/Off-Line Signatures?.- Anonymous Signatures Revisited.- Cryptographic Protocols.- An eCK-Secure Authenticated Key Exchange Protocol without Random Oracles.- Password Authenticated Key Exchange Based on RSA in the Three-Party Settings.- Comparing SessionStateReveal and EphemeralKeyReveal for Diffie-Hellman Protocols.- Zero-Knowledge Protocols for NTRU: Application to Identification and Proof of Plaintext Knowledge.- Server-Controlled Identity-Based Authenticated Key Exchange.- Reductions and Privacy.- Oracle Separation in the Non-uniform Model.- GUC-Secure Set-Intersection Computation.- Self-enforcing Private Inference Control.

This book constitutes the refereed proceedings of the Third International Conference on Provable Security, ProvSec 2009, held in Guangzhou, China, November 11-13, 2009. The 19 revised full papers and two invited talks presented were carefully reviewed and selected from 64 submissions. The papers are organized in topical sections on encryption, digital signature, cryptographic protocols and reduction and privacy.