New Release: Bouncy Castle C# .NET 2.7.0
2026-08-07
The Bouncy Castle team is pleased to announce the release of Bouncy Castle C# .NET 2.7.0, helping organizations adopt stronger security, prepare for the post-quantum era, and simplify secure application development.
This release brings extensive fixes across cryptographic components, certificate handling, TLS, CMS, OpenPGP, PKIX, and ASN.1. It also adds enhanced TLS 1.3 capabilities, new cryptographic algorithms, improved interoperability, and configurable security features.
Key Updates
Post-Quantum and Next-Generation TLS 1.3
Version 2.7.0 introduces hybrid post-quantum key exchange and post-quantum authentication for TLS 1.3, enabling developers to begin their quantum-safe migration today rather than waiting for operating system TLS implementations to catch up.
Support for hybrid ML-KEM key exchange, ML-DSA and SLH-DSA authentication, together with additional integrity-only and ShangMi cipher suites, provides a strong foundation for organizations preparing for future cryptographic requirements.
Comprehensive Security Hardening
This release includes a broad security hardening initiative designed to improve resilience against malicious inputs and side-channel attacks.
Enhanced parser protections, stronger certificate validation, constant-time implementations, and improved post-quantum decryption paths help reduce operational risk while allowing customers to benefit from stronger default security without requiring application changes.
Runtime Configuration with the Properties Utility
A new Properties utility introduces flexible runtime configuration, allowing applications to fine-tune library behavior without code changes.
Thread-local configuration, environment-variable fallback, and scoped property settings make it easier to adopt stricter security defaults while maintaining compatibility for legacy or specialized workloads.
New Algorithms and Improved Interoperability
Bouncy Castle C# 2.7.0 expands its cryptographic capabilities with support for XChaCha20, XChaCha20-Poly1305, ECGOST3410 (ECVKO), and updated HQC implementations.
The release also improves interoperability with OpenSSL, .NET certificate APIs, OpenPGP, and CMS, making it easier for developers to integrate modern cryptography while reducing reliance on external libraries and custom interoperability code.
Release Notes
For the complete list of added features, fixed security issues and defects, see:
Download
Bouncy Castle C# .NET 2.7.0 is available on NuGet and on bouncycastle.org/download.
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