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 Storages 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.
Weakness
The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Rails | Rubyonrails | * | 7.2.3.1 (excluding) |
| Rails | Rubyonrails | 8.0.0 (including) | 8.0.4.1 (excluding) |
| Rails | Rubyonrails | 8.1.0 (including) | 8.1.2.1 (excluding) |
| Rails | Ubuntu | esm-apps/xenial | * |
| Rails | Ubuntu | questing | * |
Potential Mitigations
References
- https://github.com/rails/rails/commit/2cd933c366b777f873d4d590127da2f4a25e4ba5
- https://github.com/rails/rails/commit/42012eaaa88dfc7d0030161b2bc8074a7bbce92a
- https://github.com/rails/rails/commit/8159a9c3de3f27a2bcf2866b8bf9ceb9075e229b
- 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://github.com/rails/rails/security/advisories/GHSA-r46p-8f7g-vvvg