CVE-2026-33170 (GCVE-0-2026-33170)
Vulnerability from cvelistv5
Published
2026-03-23 23:09
Modified
2026-03-25 19:20
Severity ?
5.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
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.
References
Impacted products
Vendor Product Version
rails activesupport Version: >= 8.1.0.beta1, < 8.1.2.1
Version: >= 8.0.0.beta1, < 8.0.4.1
Version: < 7.2.3.1
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