CVE Catalog

CVE-2026-33174

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Summary

Active Storage in Rails before versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, when serving files through proxy delivery mode, loads the entire requested byte range into memory before sending. A request with a large or unbounded Range header (e.g. bytes=0-) can cause memory allocation proportional to file size, possibly resulting in DoS through memory exhaustion. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Risk Assessment

An attacker can cause server memory exhaustion and denial of service via requests with unbounded byte ranges to served files.

Recommendation

Update Rails to version 8.1.2.1, 8.0.4.1, or 7.2.3.1 (or later); consider limiting Range header size at the proxy level.

Related vulnerabilities

Original NVD description (English source)

Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, when serving files through Active Storage's proxy delivery mode, the proxy controller loads the entire requested byte range into memory before sending it. A request with a large or unbounded Range header (e.g. `bytes=0-`) could cause the server to allocate memory proportional to the file size, possibly resulting in a DoS vulnerability through memory exhaustion. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS