# Traefik v2.11.57

- Product: Traefik (https://whatsnew.fyi/product/traefik)
- Vendor: Traefik Labs
- Date: 2026-09-04
- Version: v2.11.57
- Original notes: https://github.com/traefik/traefik/releases/tag/v2.11.57
- Permalink: https://whatsnew.fyi/product/traefik/releases/v2.11.57

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **fixed** — Disable recursive nss propagation by default for DNS challenge
- **fixed** — Dedicate a transport per HTTP/3 client connection
- **fixed** — Deny request with an opaque request target
- **fixed** — Do not forward h2c upgrade headers to the backend

**Important:** Please read the [migration guide](https://doc.traefik.io/traefik/v2.11/migration/v2/#v21157).

**Bug fixes:**
- **[acme]** Disable recursive nss propagation by default for DNS challenge ([#13830](https://github.com/traefik/traefik/pull/13830) @rtribotte)
- **[http3]** Dedicate a transport per HTTP/3 client connection ([#13812](https://github.com/traefik/traefik/pull/13812) @sdelicata)
- **[server]** Deny request with an opaque request target ([#13796](https://github.com/traefik/traefik/pull/13796) @sdelicata)
- **[server]** Do not forward h2c upgrade headers to the backend ([#13797](https://github.com/traefik/traefik/pull/13797) @sdelicata)