Artifact classes
I've been doing some thinking about IR and CF artifacts over the past couple of weeks, and wanted to share my thoughts on something that may be of use, particularly if its developed a bit...
When approaching many things in life, particularly a case I'm investigating, I tend to classify things (image the scene in the Matrix where Agent Smith has Morpheus captive, and tells him that he's classified the human species as a virus*) based on information I've received...incident reports, interviews with the client, etc. By classify, I mean categorizing the incident in my mind...web page defacement, intrusion/compromise, inappropriate use, etc. To some extent, I think we all do this...and the outcome of this is that we tend to look for artifacts that support this classification. If I don't find these artifacts, or the artifacts that I do find do not support my initial classification, then I modify my classification.
A by-product of this is that if I've classified a case as, say, an intrusion, I'm not necessarily going to be looking for something else, such as illicit images, particularly if it hasn't been requested by the client. Doing so would consume more time, and when you're working for a client, you need to optimize your time to meet their needs. After all, they're paying for your time.
Now, what got me thinking is that many time in the public lists (and some that require membership) I'll see questions or comments that indicate that the analyst really isn't all that familiar with either the operating system in the image, or the nature of the incident they're investigating, or both. This is also true (perhaps more so) during incident response activities...not understanding the nature of an issue (intrusion, malware infection, DoS attack, etc.) can many times leave the responder either pursuing the wrong things, or suffering from simple paralysis and not knowing where to begin.
So, understanding how we classify things in our minds can lead us to classifying events and incidents, as well as classifying artifacts, and ultimately mapping between the two. This then helps us decide upon the appropriate course of action, during both live response (ie, an active attack) and post-mortem activities.
My question to the community is this...even given the variables involved (OS, file system, etc.), is there any benefit to developing a framework for classification, to include artifacts, to provide (at the very least) a roadmap for investigating cases?
Addendum, 30 Nov: Based on an exchange going on over on FFN, I'm starting to see some thought being put into this, and it's helping me gel (albiet not crystalize, yet) up my thinking, as well. Look at it this way...doctors have a process that they go through to diagnose patients. There are things that occur every time you show up at the doctor's office (height, weight, temperature, blood pressure), and there are those things that the doctor does to diagnose your particular "issue du jour". Decisions are made based on the info the doctor receives from the patient, and courses of action are decided. The doctor will listen to the patient, but also observe the patient's reaction to certain stimuli...because sometimes patients lie, or the doctor may be asking the wrong question.
Continuing with the medical analogy, sometimes it's a doctor that responds, sometimes a nurse or an EMT. Either way, they've all had training, and they all have knowledge of the human body...enough to know what can possibly be wrong and how to react.
Someone suggested that this may not be the right framework to establish...IMHO, at least it's something. Right now we have nothing. Oh, and I get to be Dr. House. ;-)
*It's funny that I should say that...I was interviewed on 15 May 1989 regarding the issue of women at VMI, and I said that they would initially be treated like a virus.
When approaching many things in life, particularly a case I'm investigating, I tend to classify things (image the scene in the Matrix where Agent Smith has Morpheus captive, and tells him that he's classified the human species as a virus*) based on information I've received...incident reports, interviews with the client, etc. By classify, I mean categorizing the incident in my mind...web page defacement, intrusion/compromise, inappropriate use, etc. To some extent, I think we all do this...and the outcome of this is that we tend to look for artifacts that support this classification. If I don't find these artifacts, or the artifacts that I do find do not support my initial classification, then I modify my classification.
A by-product of this is that if I've classified a case as, say, an intrusion, I'm not necessarily going to be looking for something else, such as illicit images, particularly if it hasn't been requested by the client. Doing so would consume more time, and when you're working for a client, you need to optimize your time to meet their needs. After all, they're paying for your time.
Now, what got me thinking is that many time in the public lists (and some that require membership) I'll see questions or comments that indicate that the analyst really isn't all that familiar with either the operating system in the image, or the nature of the incident they're investigating, or both. This is also true (perhaps more so) during incident response activities...not understanding the nature of an issue (intrusion, malware infection, DoS attack, etc.) can many times leave the responder either pursuing the wrong things, or suffering from simple paralysis and not knowing where to begin.
So, understanding how we classify things in our minds can lead us to classifying events and incidents, as well as classifying artifacts, and ultimately mapping between the two. This then helps us decide upon the appropriate course of action, during both live response (ie, an active attack) and post-mortem activities.
My question to the community is this...even given the variables involved (OS, file system, etc.), is there any benefit to developing a framework for classification, to include artifacts, to provide (at the very least) a roadmap for investigating cases?
Addendum, 30 Nov: Based on an exchange going on over on FFN, I'm starting to see some thought being put into this, and it's helping me gel (albiet not crystalize, yet) up my thinking, as well. Look at it this way...doctors have a process that they go through to diagnose patients. There are things that occur every time you show up at the doctor's office (height, weight, temperature, blood pressure), and there are those things that the doctor does to diagnose your particular "issue du jour". Decisions are made based on the info the doctor receives from the patient, and courses of action are decided. The doctor will listen to the patient, but also observe the patient's reaction to certain stimuli...because sometimes patients lie, or the doctor may be asking the wrong question.
Continuing with the medical analogy, sometimes it's a doctor that responds, sometimes a nurse or an EMT. Either way, they've all had training, and they all have knowledge of the human body...enough to know what can possibly be wrong and how to react.
Someone suggested that this may not be the right framework to establish...IMHO, at least it's something. Right now we have nothing. Oh, and I get to be Dr. House. ;-)
*It's funny that I should say that...I was interviewed on 15 May 1989 regarding the issue of women at VMI, and I said that they would initially be treated like a virus.
