CVE-2026-33658: Rails Active Storage has a possible DoS vulnerability in proxy mode via multi-range requests
(updated )
Active Storage’s proxy controller does not limit the number of byte ranges in an HTTP Range header. A request with thousands of small ranges causes disproportionate CPU usage compared to a normal request for the same file, possibly resulting in a DoS vulnerability.
References
- github.com/advisories/GHSA-p9fm-f462-ggrg
- github.com/rails/rails
- github.com/rails/rails/releases/tag/v7.2.3.1
- github.com/rails/rails/releases/tag/v8.0.4.1
- github.com/rails/rails/releases/tag/v8.1.2.1
- github.com/rails/rails/security/advisories/GHSA-p9fm-f462-ggrg
- github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2026-33658.yml
- nvd.nist.gov/vuln/detail/CVE-2026-33658
Code Behaviors & Features
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