rails 8.1.2.1

on Ruby Gems

Active Support

• Reject scientific notation in NumberConverter

  [CVE-2026-33176]

  Jean Boussier

• Fix SafeBuffer#% to preserve unsafe status

  [CVE-2026-33170]

  Jean Boussier

• Improve performance of NumberToDelimitedConverter

  [CVE-2026-33169]

  Jean Boussier

Active Model

• No changes.

Active Record

• No changes.

Action View

• Skip blank attribute names in tag helpers to avoid generating invalid HTML.

  [CVE-2026-33168]

  Mike Dalessio

Action Pack

• Fix possible XSS in DebugExceptions middleware

  [CVE-2026-33167]

  John Hawthorn

Active Job

• No changes.

Action Mailer

• No changes.

Action Cable

• No changes.

Active Storage

• Filter user supplied metadata in DirectUploadController

  [CVE-2026-33173]

  Jean Boussier

• Configurable maxmimum streaming chunk size

  Makes sure that byte ranges for blobs don't exceed 100mb by default.
  Content ranges that are too big can result in denial of service.

  [CVE-2026-33174]

  Gannon McGibbon

• Limit range requests to a single range

  [CVE-2026-33658]

  Jean Boussier

• Prevent path traversal in DiskService.

  DiskService#path_for now raises an InvalidKeyError when passed keys with dot segments (".",
  ".."), or if the resolved path is outside the storage root directory.

  #path_for also now consistently raises InvalidKeyError if the key is invalid in any way, for
  example containing null bytes or having an incompatible encoding. Previously, the exception
  raised may have been ArgumentError or Encoding::CompatibilityError.

  DiskController now explicitly rescues InvalidKeyError with appropriate HTTP status codes.

  [CVE-2026-33195]

  Mike Dalessio

• Prevent glob injection in DiskService#delete_prefixed.

  Escape glob metacharacters in the resolved path before passing to Dir.glob.

  Note that this change breaks any existing code that is relying on delete_prefixed to expand
  glob metacharacters. This change presumes that is unintended behavior (as other storage services
  do not respect these metacharacters).

  [CVE-2026-33202]

  Mike Dalessio

Action Mailbox

• No changes.

Action Text

• No changes.

Railties

• No changes.

Guides

• No changes.