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Details of issue NIXPKGS-2026-0744

NIXPKGS-2026-0744
published on 24 Mar 2026
updated 15 hours ago by @LeSuisse Activity log
  • Created automatic suggestion
  • @LeSuisse removed
    4 packages
    • rubyPackages.yard-activesupport-concern
    • rubyPackages_3_3.yard-activesupport-concern
    • rubyPackages_3_4.yard-activesupport-concern
    • rubyPackages_4_0.yard-activesupport-concern
  • @LeSuisse accepted
  • @LeSuisse published on GitHub
Rails Active Support has a possible XSS vulnerability in SafeBuffer#%

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `SafeBuffer#%` does not propagate the `@html_unsafe` flag to the newly created buffer. If a `SafeBuffer` is mutated in place (e.g. via `gsub!`) and then formatted with `%` using untrusted arguments, the result incorrectly reports `html_safe? == true`, bypassing ERB auto-escaping and possibly leading to XSS. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Affected products

activesupport
  • ==< 7.2.3.1
  • ==>= 8.1.0.beta1, < 8.1.2.1
  • ==>= 8.0.0.beta1, < 8.0.4.1

Matching in nixpkgs

Ignored packages (4)
Upstream advisory: https://github.com/rails/rails/security/advisories/GHSA-89vf-4333-qx8v