CVE-2026-33170
Published: Mar 23, 2026
Modified: Mar 25, 2026
Description
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.
| Vendor | Product | Versions |
|---|---|---|
rails | activesupport | affected >= 8.1.0.beta1, < 8.1.2.1affected >= 8.0.0.beta1, < 8.0.4.1affected < 7.2.3.1 |
Weaknesses (CWE)
References
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