Rails Active Support has a possible XSS vulnerability in SafeBuffer#%

TRUNG BÌNH 6.1CVE-2026-33170 · GHSA-89vf-4333-qx8v · Công bố 24/03/2026 · cập nhật 17/06/2026

Gói / sản phẩm	Phiên bản bị ảnh hưởng	Phiên bản đã vá
activesupport RubyGems	`≥ 8.0.0.beta1, < 8.0.4.1≥ 8.1.0.beta1, < 8.1.2.1< 7.2.3.1`	`8.0.4.18.1.2.17.2.3.1`
rails rubyonrails	`≥ 8.0.0, < 8.0.4.1≥ 8.1.0, < 8.1.2.1< 7.2.3.1`	`8.0.4.18.1.2.17.2.3.1`

Mô tả

Impact

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.

Releases

The fixed releases are available at the normal locations.

Credit

This issue was responsibly reported by @ch4n3-yoon

Mô tả của NVD

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.