Traefik v2.11.58 has been released on the maintenance branch, and it is a pure bug-fix cut: no new features, no breaking changes. The patch touches several subsystems at once — the Docker provider, routing-rule parsing, TLS handling on the server side, service transports and UDP proxying — which makes it a worthwhile upgrade for anyone running the v2.11 line in production.
- [docker] Bumped
github.com/docker/clito v29.8.1, keeping the provider aligned with upstream client changes (#13934). - [rules] Negated matchers are now ignored when parsing rule domains, avoiding incorrect domain extraction from rules such as those using
!matchers (#13863). - [server] Upgraded
golang.org/x/cryptoto v0.57.0 (#13930) and ensured the request TLS state is always populated for downstream consumers (#13985). - [service] A dedicated sticky transport is now allocated per
ServersTransport, preventing transport sharing across configurations (#13838). - [service] Pre-authenticated NTLM and Kerberos backend connections are now isolated, so credentials are not leaked or reused between distinct backends (#13902).
- [udp] UDP datagrams are copied into right-sized buffers before being queued, tightening memory behaviour under load (#13941).
Why it matters for developers: each fix targets a class of subtle production bugs rather than cosmetic issues. The ServersTransport sticky-transport isolation and the NTLM/Kerberos connection isolation directly affect request correctness when multiple backends or authenticated sessions coexist — scenarios where shared connection state can produce confusing cross-talk. Always setting the request TLS state removes a source of nil-state surprises in middleware and plugins that inspect request.TLS. The UDP buffer-sizing change reduces allocation churn and the risk of oversized queues on busy datagram paths, while the rules fix stops negated matchers from polluting parsed domains. If you build on Traefik’s Docker provider, custom rules, or authenticated backends, upgrading to v2.11.58 is a low-risk way to pick up these hardening improvements.
Source: https://github.com/traefik/traefik/releases/tag/v2.11.58