# Ruby 4.0.3 — Ruby 4.0.3 Released

- Product: Ruby (https://whatsnew.fyi/product/ruby)
- Vendor: Ruby
- Date: 2026-04-21
- Version: 4.0.3
- Original notes: https://www.ruby-lang.org/en/news/2026/04/21/ruby-4-0-3-released/
- Permalink: https://whatsnew.fyi/product/ruby/releases/4.0.3

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Ruby 4.0.3 has been released. This release only contains ERB 6.0.1.1, which fixes CVE-2026-41316 . If your application calls Marshal.load on untrusted data AND has both erb and activesupport loaded, p…

- **security** — Fix CVE-2026-41316 in ERB 6.0.1.1