GHSA-89vf-4333-qx8vMedium
Rails Active Support has a possible XSS vulnerability in SafeBuffer#%
🔗 CVE IDs covered (1)
📋 Description
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
🎯 Affected products3
- rubygems/activesupport:>= 8.1.0.beta1, < 8.1.2.1
- rubygems/activesupport:>= 8.0.0.beta1, < 8.0.4.1
- rubygems/activesupport:< 7.2.3.1
🔗 References (10)
- https://github.com/rails/rails/security/advisories/GHSA-89vf-4333-qx8v
- https://github.com/rails/rails/commit/50d732af3b7c8aaf63cbcca0becbc00279b215b7
- https://github.com/rails/rails/commit/6e8a81108001d58043de9e54a06fca58962fc2db
- https://github.com/rails/rails/commit/c1ad0e8e1972032f3395853a5e99cea035035beb
- https://github.com/rails/rails/releases/tag/v7.2.3.1
- https://github.com/rails/rails/releases/tag/v8.0.4.1
- https://github.com/rails/rails/releases/tag/v8.1.2.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-33170
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activesupport/CVE-2026-33170.yml
- https://github.com/advisories/GHSA-89vf-4333-qx8v