Forensics & The Fabled Chain Of Custody

I’m not very big into forensics any more, but occasionally I’ll get asked to take on a case or two, and whenever I do, the one thing that people always manage to seem to get wrong is the chain of custody.

Now for those of you who have no idea what I’m talking about here, here is the blurb from Wikipedia on Chain Of Custody.

Chain of custody (CoC) refers to the chronological documentation or paper trail, showing the seizure, custody, control, transfer, analysis, and disposition of evidence, physical or electronic. Because evidence can be used in court to convict persons of crimes, it must be handled in a scrupulously careful manner to avoid later allegations of tampering or misconduct which can compromise the case of the prosecution toward acquittal or to overturning a guilty verdict upon appeal. The idea behind recording the chain of custody is to establish that the alleged evidence is in fact related to the alleged crime, rather than having, for example, been planted fraudulently to make someone appear guilty.”

I have seen so many cases through the years, where a single has just gone and asked a user to please shutdown their PC, and then taken it away from them, jumped in a cab, and as it was late, taken the PC home with them for the night. Then the next morning, they’ll walk into my office and ask me to do forensics on the host, as the user in question has been doing x,y and z wrong on company property and they want to fire them and prosecute. It’s very hard trying to explain to senior management, that while, I can do the forensics for you, and I’m sure that I’ll find something, can you please just prove to me that you didn’t put it there to frame the person? This usually results with the same old conversation, that kind of goes along these lines.

Manager: “Of course I didn’t put it there! I’m a senior manager, why would I do that, what do I stand to gain?”

Me: “Well, it could be that you just don’t like this person, or on a personal level, they’ve done something to upset you”

Manager: “Well, I’m telling you that I didn’t put anything on his PC, and I’m a senior manager! So get started with the forensics asap, and let me know!”

Me: “You seem very defensive, it sounds like you may be hiding something?”

Manager: “I am not hiding anything, I just want you to prove that he was doing something wrong so that I can fire him and then get legal to prosecute!”

Me: “Okay, I’ll do what I’ve been asked. Just remember though, I’m a IT Security guy, and you sound guilty to me, even though you may not be, imagine what a lawyer would do with you? We have forensics procedures, that are visible to the entire company in regards to bringing in user’s PC’s, next time can you please take the time to read these?”

The senior manager then usually storms out of the office.

Following proper procedures for forensics purposes is of the utmost importance, as if you do need to lay charges you need to be able to prove that you did everything by the book. If you don’t have detailed procedures for your in-house forensics, maybe now is the time to start thinking about writing some…

National Strategy for Trusted Identities in Cyberspace

There is no possible way this could potentially go wrong, right?

Doesn’t the phrase “Identity Ecosystem” make you feel all warm and “green”?

It’s a public/private partnership, right?  So there is no possibility of some large corporation taking over the process and imposing *their* management ideas on it?  Like, say, trying to re-introduce the TCPI?

And there couldn’t possibly be any problem that an identity management system is being run out of the US, which has no privacy legislation?

The fact that any PKI has to be complete, and locked down, couldn’t affect the outcome, could it?

There isn’t any possible need for anyone (who wasn’t a vile criminal) to be anonymous, is there?

KHOBE: Say hello to my little friend(*)

Guess what? You personal firewall/IDS/Anti Virus/(insert next month’s buzzword here) isn’t going to save you from an attacker successfully executing code remotely on your machine:

So no, it’s not the doomsday weapon, but definitely worthy of the Scarface quote in the title.
This isn’t surprising, researchers find ways to bypass security defenses almost as soon as those defenses are implemented (remember non-executable stack?). Eliminating vulnerabilities in the first place is the way to go, guys, not trying to block attacks hoping your ‘shields’ hold up.

(*) If you’re reading this out loud you need to do so in a thick cuban accent

Printers, the forgotten threat.

It seems that in this day and age, people have finally grasped the concepts of why it’s a good idea to patch systems regularly, run an anti-virus application, and have funky network appliances like firewalls and Intrusion Detection Systems. Which is a really great move in the right direction.

One thing that I will never understand though is that people will spend a fortune on new security tools and appliances, adn they’ll forget the basics.

Please people, remember to lock down the items on your network that may seem insignificant to you, as nine out of ten times, they are a foothold for a hacker. A prime example of this would be printers, I have managed to obtain really sensitive information off of printers attached to networks in their default state in the past, and also waste valuable time and company resources.

Here are few of the things that i’ve done on various assignments over the years in regards to printers:

– Modify the default web console pages, and load them up with browser exploits

– Find valuabe documents saved as files on the printers

– Use the printers as zombie hosts for nmap zombie network scans

– Tie up the printer for a day or so printing out the contents of my hard drive

– Waste paper and ink from doing the above

– Leave obscene messages on the console display
– Shut down the printer and fake the logon page to accomplish all of the above

Here’s a pretty useful link for all those with HP printers on their estate as well.
So in going forward, please remember that if it’s attached to your network, it needs to be secured. Most printers these days come with security configuration options, but they have to be enabled, so take the extra 5 minutes to make the world a better place.