# Fastify v5.12.2

- Product: Fastify (https://whatsnew.fyi/product/fastify)
- Vendor: Fastify
- Date: 2026-09-04
- Version: v5.12.2
- Original notes: https://github.com/fastify/fastify/releases/tag/v5.12.2
- Permalink: https://whatsnew.fyi/product/fastify/releases/v5.12.2

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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- **security** — Fix for GHSA-9q9j-q6p8-xq58
- **security** — Fix for GHSA-hwr6-493r-vm6h
- **security** — Fix for GHSA-p68q-wchp-6fh7
- **security** — Fix for GHSA-667r-xxjv-c9mm
- **fixed** — callNotFound should run not-found preHandler regardless of registration order

##### ⚠️ Security release

* Fix for https://github.com/fastify/fastify/security/advisories/GHSA-9q9j-q6p8-xq58
* Fix for https://github.com/fastify/fastify/security/advisories/GHSA-hwr6-493r-vm6h
* Fix for https://github.com/fastify/fastify/security/advisories/GHSA-p68q-wchp-6fh7
* Fix for https://github.com/fastify/fastify/security/advisories/GHSA-667r-xxjv-c9mm

##### What's Changed
* [Backport 5.x] fix: callNotFound should run not-found preHandler regardless of registration order by @github-actions[bot] in https://github.com/fastify/fastify/pull/6973
* [Backport 5.x] chore: npm ignore remaining agent files by @github-actions[bot] in https://github.com/fastify/fastify/pull/7003


**Full Changelog**: https://github.com/fastify/fastify/compare/v5.12.1...v5.12.2