Let me just say this: it seemed like a good choice at the time, and, if I could have trusted the vendor to deploy the software on it properly, it might still be. Here is a short summary of some of the issues I found:

You can skip to the full report here: A Security Audit of the Synology Disk Station Manager (DSM) v2.0-0590 Firmware.

What follows is a complete retelling of how I got here, sort of a lesson in vulnerability disclosure (not so much discovery, you’ll see why). It’s not pretty, I didn’t do all the right things, and it’s kind of long.

I had a lot of free time over Spring break (read: no money to travel anywhere) and so I decided to start “kicking the tires” of the Synology CS407 I owned. My jaw dropped when I got this first nmap scan back:

PORT      STATE SERVICE     VERSION
80/tcp    open  http        Apache httpd 2.2.3 ((Unix) mod_ssl/2.2.3 OpenSSL/0.9.7e PHP/5.2.0)
139/tcp   open  netbios-ssn Samba smbd 3.X (workgroup: WORKGROUP)
443/tcp   open  http        Apache SSL-only mode httpd
445/tcp   open  netbios-ssn Samba smbd 3.X (workgroup: WORKGROUP)
515/tcp   open  printer
548/tcp   open  afpovertcp?
3306/tcp  open  mysql       MySQL (unauthorized)
3493/tcp  open  tcpwrapped
3689/tcp  open  http        mt-daapd httpd 0.2.4
5000/tcp  open  http        Apache httpd 2.2.3 ((Unix) mod_ssl/2.2.3 OpenSSL/0.9.7e)
5001/tcp  open  http        Apache SSL-only mode httpd
5432/tcp  open  postgresql  PostgreSQL DB
50001/tcp open  tcpwrapped

It only got worse when I ran Nessus. And then worse when I got a shell and started poking around the filesystem. Get this: every application on the box is running as root! And all the web apps are written as compiled binaries running in CGI… with root privileges! As a friend in the lab described it, “1996 called, it wants its web technology back!” They weren’t even making it difficult.

This is where things got interesting. I looked around and there isn’t any formal security contact or even a public bug tracker (and they call themselves a Linux vendor!). I’m thinking maybe I can save myself some trouble and get this solved informally, so I made this really scary sounding post on their user support forums with just the results of that nmap scan. I also submitted a technical support request at the same time, pointing to the forum post. Best idea? No. But it was easy. I really didn’t want to write a formal report and submit it. I’m not getting paid for this, and frankly, I’m kind of pissed off that I bought this thing and that I’m stuck with it now.

Two moderators immediately replied to my forum post claiming that there were no security vulnerabilities and that security vulnerabilities were the price we pay for having the coolest NAS out there. I thought these were official representatives of Synology at first and was ready to make a post to full-disclosure after reading their replies.

Then an official response came back from their tech support: log in to the box over SSH (which they don’t provide, I had to hack it to turn it on) and turn off the affected services. They also recommended I put the box behind a firewall… This is why you’re supposed to have a security@ contact, so people like me don’t get stuck with non-tech and sales staff. I said a few specific things in my reply to get my concerns in front of the right people:

1. Ask for this issue to be escalated to a product manager
2. Explain the risks they were putting themselves and their customers under
3. Explain what would happen if they didn’t respond to my concerns (full-disclosure)
4. Included a PDF of a very early draft of my report

That worked. 3 days later I got a response from Synology (still their sales staff) indicating that more than half of the vulnerabilities I pointed out would get fixed in a new release of the firmware due out in 60 days. They denied a number of vulnerabilities, which I explained further and sent back to them.

Then I didn’t hear from them for 9 days. Apparently, my emails were getting stuck in their spam filter (again, vendors, please set up a security@ e-mail)! This went back and forth for a bit and I’ve moved about 90% of the issues into the next release! A handful of more architectural issues were pushed back until a release 6 months in the future. You can’t win them all, but at least they are aware of the issues now.

Back on the forum, I had been getting fairly actively involved by answering security questions from other users. Some intelligent people saw what I was saying and came to my defense when the fanboys attacked what I was saying about their precious devices. Two people even posted that they had delayed or reconsidered buying Synology products because of this discussion! It was really great to hear that, both as vindication that what I was saying was important and that Synology’s management had to take me seriously now. They were actively losing customers due to poor development practices.

How they reacted to this really isn’t surprising in hindsight: they moved all my posts to a separate, special forum, away from potential and current (but mostly potential) customers. Then their moderators started getting fed up that people were still talking about security issues they thought were irrelevant and resorted to character attacks and flaming. I sent an e-mail to my contact on the sales staff that someone representing their company was acting inappropriately and their behavior might be tied back to the company. Synology responded by locking my post.

And that’s the end of that mess.

If you have a Synology product… well good luck! All the problems I found won’t be resolved until 09/2008! And even then, I’m sure there will be more security vulnerabilities. Those compiled binary CGIs are a ticking timebomb. If you don’t already own a Synology product, I suggest FreeNAS. You can install it in a VM and try it before you “buy” it. I’d really like to get my hands on one of NetGear’s ReadyNAS products… anyone with one want to let me poke around it for a bit?

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