ActiveSupport::EncryptedFile writes contents that will be encrypted to a temporary file. The temporary file's permissions are defaulted to the user's current `umask` settings, meaning that it's possible for other users on the same system to read the contents of the temporary file. Attackers that have access to the file system could possibly read the contents of this temporary file while a user is editing it. All users running an affected release should either upgrade or use one of the workarounds immediately.
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.