stunnel 5.76 for Mission-Critical TLS

Upgrade legacy systems to modern, post-quantum–ready TLS with zero refactoring

Worksters delivers and supports stunnel in production, so your teams can ship faster and more securely.

Why this matters

• Future-proof security – Hybrid X25519+ML-KEM-768 key agreement on OpenSSL 3.5+ with TLS 1.3

• Fallback-ready – Works with non-PQC peers

• FIPS-aware – PQC not yet available in FIPS mode until validated

• TLS 1.3 performance – Fast handshakes, hardened defaults

• Flexible identity – mTLS with X.509 or TLS-PSK

• Scalable revocation – OCSP and stapling for large deployments

Where we help

• Priority engineering support from stunnel developers

• Sponsor roadmap features or custom hardened builds

• Drop-in encryption for legacy, OT, and ICS

• Hybrid post-quantum TLS pilots (no code changes)

• Programs for long-term data confidentiality and compliance

CNG Provider for OpenSSL on Windows

Use Windows keys and certificates with OpenSSL — no code changes

Worksters delivers the CNG Provider so you can retain your Windows security model and OpenSSL tools.

What you get

• Fast rollout using existing Windows certs, smart cards, TPMs, HSMs

• Lower risk – keys stay in Windows (no exports)

• Modern TLS – clean mutual TLS for stunnel and others

• Works alongside your existing OpenSSL setup

• Stronger compliance fit for federal and enterprise environments

Where it fits

• Enterprise mTLS on Windows

• Hardware-backed production key use

• Replacing fragile engine integrations

Where we help

• Deployment support for PKI, cert stores, HSMs, smart cards

• Runbooks, checklists, and operator training

• Patch/lifecycle management including LTS binaries

• Support tiers with SLAs, hotfixes, and escalation paths

• Interoperability testing with OpenSSL-based tools

• Security hardening and baseline configurations

• Custom builds and PKI integrations