OSAS - Open Storage Account Scanner ;)

First off, this is not a polished project. If you are expecting a turn-key solution, you're going to be very disappointed. Even if you are not expecting a turn-key solution, you'll probably still be disappointed.

This was hacked together for a personal project of mine to grab a random sampling of Azure storage accounts and see how many were wide open. Similar to the various AWS S3 bucket scanners out there, this simply looks for any storage account blob containers that have been left open, and then stores the results in a database. There are also some utility tools to help dig through the data.

OSAS has been re-factored to ship as an all-in-one tool vs multiple specific tools, hopefully making it easier to use. In the current form there are three supported commands:

• list: list contents, and optionally download those contents, of an open blob container
• load: load a list of targets into the database
• scan: this is the actual application that does the scanning

Your typical workflow might look something like this:

• use list to load in a list of targets. These will be the storage accounts you want to scan and you just need the name, OSAS will tack on the ".blob.core.windows.net" for you, so you just need to provide the actual storage account name.
• use scan to scan the target(s). scan will use the word list you give it and check each entry to see if it is an open blob container in the storage account (blah.blob.core.windows.net/1, blah.blob.core.windows.net/2, blah.blob.core.windows.net/3, etc)
• use list to see what goodies you found :)

You fire up however many scan instances you want, and then you can use list to display the contents of the open blob containers scan finds.

As everything is stored in a database, the automation possibilities are pretty big. Maybe automate the calling of list on open accounts and store those results in another table? Maybe take those results and, based on file type, do some OCR?

Install & Setup

You'll need a MySQL (or whatever they call it these days) database and two tables:

CREATE TABLE stg_accts (
  url VARCHAR(2083) NOT NULL,
  last_check datetime NOT NULL,
  is_open tinyint(1)  NOT NULL
);


CREATE TABLE open_containers (
  url VARCHAR(2083) NOT NULL,
  last_check datetime NOT NULL
);

The stg_accts table is going to be a list of URLs you want to scan, this is where the load command will insert your targets. When the app starts, it'll hit that table, find the oldest record and start scanning it. If it finds that it is open, it will update the table PLUS put whatever results it finds into the open_containers table.

You can install OSAS via go install github.com/esell/OSAS@latest if you already have go installed. No pre-built binaries are available yet :(.

There is a sample config.json that shows you what your config should look like.

Usage

Using this is pretty straightforward and doing an OSAS -h is probably the best way to get going. One thing to keep in mind is that scan is reading in a list of targets from the database, so this is meant as more of a bulk scanning type tool. Feel free to fire up multiple instances of scan to work through your target list more quickly.