CVE-2026-33174
highpriority · track · 30EPSS 0.006 · 50 %ileDEEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (21)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-0833Ruby on Rails: Mehrere SchwachstellenDeutsch2026-03-23csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Ruby on Rails ausnutzen, um einen Denial of Service Angriff durchzuführen, um Dateien zu manipulieren, und um einen Cross-Site Scripting Angriff durchzuführen.
- WID-SEC-W-2026-1687IBM License Metric Tool: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2026-05-26csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM License Metric Tool ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
- GHSA-r46p-8f7g-vvvgRails Active Storage has a possible DoS vulnerability when in proxy mode via Range requests2026-03-23ghsa · osvUS
### Impact When serving files through Active Storage's `Blobs::ProxyController`, the 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. ### Releases The fixed releases are available at the normal locations. ### Credit This issue was responsibly reported by Hackerone user [pirikara](https://hackerone.com/pirikara)
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (23)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-33174cnnvd
- https://github.com/rails/rails/commit/2cd933c366b777f873d4d590127da2f4a25e4ba5cnnvd
- https://github.com/rails/rails/commit/42012eaaa88dfc7d0030161b2bc8074a7bbce92acnnvd
- https://github.com/rails/rails/commit/8159a9c3de3f27a2bcf2866b8bf9ceb9075e229bcnnvd
- https://github.com/rails/rails/releasesPatchcnnvd
- https://github.com/rails/rails/releases/tag/v7.2.3.1cnnvd
- https://github.com/rails/rails/releases/tag/v8.0.4.1cnnvd
- https://github.com/rails/rails/releases/tag/v8.1.2.1cnnvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan