Musings on Database Security

As promised, here is a small Python script to allow you to enumerate and find Oracle SIDs.

Of course, the usual caveats apply – if it breaks something, I’m not responsible Use at your own risk. I’m using the sidlist.txt file from David’s OAK but there are plenty of available resources with common SID lists.

Update: Alex graciously let me know that he was the one that originally created the SID list and also granted me permission to use his latest version with the script.

Here are some usage details:

slavik@slavik-laptop:~/Oracle/Security/osid-enum$ ./osid-guess.py
Usage: osid-guess.py [options]

osid-guess.py: error: You must provide the host of the listener

slavik@slavik-laptop:~/Oracle/Security/osid-enum$ ./osid-guess.py -h

Usage: osid-guess.py [options]
Try to find the Oracle SID iterating a list of potential SIDs from a file or from stdin
Options:
 --version             show program's version number and exit
 -h, --help            show this help message and exit

 Target options: Specify the location of the listener
 -t HOST, --host=HOST                The host running the listener
 -p PORT, --port=PORT                The port of the listener [1521]
 -s SIDLIST, --sidlist=SIDLIST       The filename containing the sids to try [stdin if missing]

 End user details: Specify end user details to send to the listener
 -u USER, --user=USER The user to provide to the listener [SCOTT]
 -a PROGRAM, --program=PROGRAM       The program name to provide to the listner [sqlplus]
 -m MACHINE, --machine=MACHINE       The name of the machine to provide to the listener [localhost]

 General options: General options to control verbose output, etc.
 -q, --quiet                         don't print status messages to stdout [output progress to stdout by default]

slavik@slavik-laptop:~/Oracle/Security/osid-enum$ ./osid-guess.py -t
localhost
Receiving service names from stdout
Opening connection to localhost:1521
test
Trying SERVICE_NAME - test
Trying SID - test
aaa
Trying SERVICE_NAME - aaa
Trying SID - aaa
db11200
Trying SERVICE_NAME - db11200
Listener supports service db11200
Trying SID - db11200
Listener supports sid db11200

On *nix, you need to press Ctrl-D between names

slavik@slavik-laptop:~/Oracle/Security/osid-enum$ ./osid-guess.py -t
localhost -s sid.txt -q
Listener supports service DB11200
Listener supports sid DB11200

So, that’s it. A very simple utility that does not have any pre-requisites (except Python, of course).

I’d love to hear some feedback…

Sumit Siddarth (Sid) has published an excellent whitepaper talking about hacking Oracle from the web. It shows many types and techniques of SQL injection and how to use an SQL injection vulnerability as a jumping point to extract data, take control of the database and even escape the database to the OS.

Security folks and DBAs out there, this is a must read!

I had a great time at RMOUG this year. Did one of my usual presentation about attack vectors on the database and how to defend against them. I think the presentation was well received and the attendees loved the demos – I mostly just demonstrate instead of going through slides.

One of my favorite demos is what I call “from nothing to DBA in 5 simple steps”.
Basically, I start with finding databases (using tools like nmap), guessing the SID, enumerating the usernames, attacking the password and then running one of the privilege escalation attacks. Of course, there are many other options, including attacking the listener instead or sniffing the network but I find that this demo usually sets the right mood for the rest of the presentation.

In some of my next posts, I’m going to publish some of the scripts I wrote for the above demo starting with a nice little script to enumerate and guess Oracle service names.

A picture of people arriving before the presentation (click to see the full picture)…

People arriving to my presentation

A really well written blog post from Mike Smithers about the need to validate data from all sources – also coming from the database.

Good one…

As part of my continued crusade to get rid of all database errors returned from the application to the user, one of our developers sent me the following error message coming from Salesforce.com:

So, what can we learn from the error?

• SF uses Java as a backend
• SF uses Oracle as the database
• The application is programmed using stored program units – in this case package sLead with procedure update_leads
• Checks are performed at the PL/SQL level and custom exceptions are being thrown – ORA-20096
• The Java application uses bind variables to call into the PL/SQL layer – good for them!
• My guess is that the username/schema for this particular SF account is SNEEZY and it contains Oracle types with the names CUSER and SLEAD

All in all, I’d say that SF did a good, secure job in implementing the application (bind variables, etc.) but missed the “never return DB errors to the customer” part.

So, what will it take to educate developers not to display errors? Thoughts?

Yesterday at Black Hat, David released information on his latest find, a pretty serious batch of vulnerabilities in Oracle 11g which allows any user to escalate privileges to gain complete access & control of the database.

What’s interesting here is not so much that there is yet another vulnerability  (for those of you who are running Hedgehog and getting vPatch updates, you are already protected!), but more how this demonstrates the very tricky relationship that often exists between ethical security researchers and the database vendors.

David has been contributing to the Oracle DB security research community for many years, and certainly has the process down pretty well for notifying Oracle and giving them time to make the fix before going public.  But, this time around, things didn’t go as planned.  After notifying Oracle in November, he apparently wasn’t satisfied with their response, and decided it was best to announce the vulnerability now.  The good news is he also provided recommendations on how to protect systems from being exploited.

We know how he feels.  In 6 out of the last 7 Oracle CPUs, one or more Sentrigo employees has been credited for contributions.  Pretty impressive for our size, and a testament to the work of our Red Team.  In all of those cases, we’ve been pretty satisfied with the pace of Oracle fixes, and have simply built protection into our products from our day-zero discovery and waited for Oracle to release a patch.

But, for those of you who have been reading this blog for a while, you’ll recall the incident last September, when after a year of prodding Microsoft to fix a flaw in SQL Server, we too reached a point of frustration and announced it.  Also, with a fix of course.  But, the decision to do this is not an easy one.  The very vendors you are hoping to have an excellent working relationship with, are not likely to be happy.  In this case, Microsoft tried to argue that it was not very serious… but as security researchers we simply didn’t agree (nor did most of the public based on comments we received).  I’m sure David felt the same way about this recent vulnerability.  You can’t simply leave it there for other (less ethical) people to find and exploit.

So, we’ll see how this one plays out… I’m guessing Oracle will eventually provide a patch.  But, it does raise the question of what the white hats of the world are supposed to do, when a vendor simply doesn’t get it.  I’d be interested in your thoughts…