Technology
OpenSSL 4.1.0 adds DTLS 1.3 and post-quantum cryptography optimisations
OpenSSL 4.1.0 is a feature release adding DTLS 1.3, GREASE support, IKEv2 key derivation and initial support for the Elbrus2000 architecture. It also optimises ML-DSA and ML-KEM operations on selected processors and changes the tsget utility’s curl dependency. Maintainers should review removed platform targets and configuration options before upgrading. The release documents several DTLS 1.3 listener and retransmission defects, including failures that can misreport connection state or drop outstanding records; a fix is planned for one issue in a future release.
Editorial summary · Publisher article
What matters
- The release adds DTLS support to the SSL listener API.
- Windows-on-Itanium and Windows CE build targets have been removed.
- Users of tsget must install Net::Curl::Easy after upgrading.
- Several documented DTLS defects affect retransmission and error handling.
Context & caveats
- The release notes identify known DTLS issues that may matter to production deployments.
Why this made the edition
The official release provides concrete compatibility changes, new protocol support, performance work and known defects relevant to software maintainers. Its practical importance is narrower than a security emergency but the evidence is primary and specific.
Source material