Activestorage

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 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. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Published: 2026-03-26T21:03:25.319Z
Updated: 2026-03-30T11:42:24.885Z

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, Active Storage's `DiskService#delete_prefixed` passes blob keys directly to `Dir.glob` without escaping glob metacharacters. If a blob key contains attacker-controlled input or custom-generated keys with glob metacharacters, it may be possible to delete unintended files from the storage directory. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Published: 2026-03-23T23:34:52.715Z
Updated: 2026-03-24T15:44:19.018Z

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, Active Storage's `DiskService#path_for` does not validate that the resolved filesystem path remains within the storage root directory. If a blob key containing path traversal sequences (e.g. `../`) is used, it could allow reading, writing, or deleting arbitrary files on the server. Blob keys are expected to be trusted strings, but some applications could be passing user input as keys and would be affected. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Published: 2026-03-23T23:31:41.785Z
Updated: 2026-03-25T03:56:06.239Z

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.

Published: 2026-03-23T23:24:55.594Z
Updated: 2026-03-24T13:40:32.031Z

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, `DirectUploadsController` accepts arbitrary metadata from the client and persists it on the blob. Because internal flags like `identified` and `analyzed` are stored in the same metadata hash, a direct-upload client can set these flags to skip MIME detection and analysis. This allows an attacker to upload arbitrary content while claiming a safe `content_type`, bypassing any validations that rely on Active Storage's automatic content type identification. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Published: 2026-03-23T23:21:29.843Z
Updated: 2026-03-24T15:12:50.569Z

# Active Storage allowed transformation methods potentially unsafe Active Storage attempts to prevent the use of potentially unsafe image transformation methods and parameters by default. The default allowed list contains three methods allow for the circumvention of the safe defaults which enables potential command injection vulnerabilities in cases where arbitrary user supplied input is accepted as valid transformation methods or parameters. Impact ------ This vulnerability impacts applications that use Active Storage with the image_processing processing gem in addition to mini_magick as the image processor. Vulnerable code will look something similar to this: ``` <%= image_tag blob.variant(params[:t] => params[:v]) %> ``` Where the transformation method or its arguments are untrusted arbitrary input. All users running an affected release should either upgrade or use one of the workarounds immediately. Workarounds ----------- Consuming user supplied input for image transformation methods or their parameters is unsupported behavior and should be considered dangerous. Strict validation of user supplied methods and parameters should be performed as well as having a strong [ImageMagick security policy](https://imagemagick.org/script/security-policy.php) deployed. Credits ------- Thank you [lio346](https://hackerone.com/lio346) for reporting this!

Published: 2026-01-30T20:11:15.219Z
Updated: 2026-02-02T14:47:12.620Z