OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

cti-stix message

[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]


Subject: Re: [cti-stix] STIX: Messaging Standard vs. Document Standard


And yes, my rant I just posted is in violent agreement with Terry’s observation and cool graphic!

On Nov 30, 2015, at 4:02 PM, Terry MacDonald <terry@soltra.com> wrote:

“There is no actual reason that indicator or sighting messages need to be a layer on top of the ontology. They are for totally different use cases and can be developed completely independently.”

 

There needs to be a relationship between the Indicators and sightings that are exchanged and the higher-order threat intelligence that is exchanged, or there is no way to relate the two levels together. The key important part in all of this is to be able to maintain relationships from one to the other. Without that ability then there is no way to do the analysis.

 

Frode Hommedal put it best in his presentation to FIRST: http://frodehommedal.no/presentations/first-tc-oslo-2015. I implore you to read it if you haven’t already. Especially this slide.

 

As I see it the two camps fall into these broad groups:

·         All of STIX: Threat Intelligence group

o   “We need to track everything otherwise we won’t be able to understand the bad guys”

o   “Everything is related to everything”

·         Indicators and Sightings: Incident Response group

o   “We don’t need to understand them, we just need to detect them damn it”

o   “I only care about Indicators and Sightings”

 

The thing that not many people realize is that you need both, and you need a way of crossing from one to the other. I think this diagram I created (©Threatloop.com) demonstrates why:

 

<image001.png>

 

The Incident Response process needs to know what Indicators are the ones that your Organization needs to look for. At present monitoring and detection systems are struggling to operate with the number of indicators they need to be looking for. The Threat intelligence process knows what threats are most likely…. So wouldn’t it be sensible to use the Threat Intelligence process to generate/filter the Indicators so that the Incident Response process has a far smaller number of things and more important things to look for?

 

And the Threat Intelligence process need to know what the Incident Response process is seeing. Maybe there is a new Threat Actor in town? Maybe an existing Threat Actor is starting a new campaign? Threat Intelligence processes need to be able to record what is happening to be able to generate Indicators that make sense and follow what the real risks to the Organization are.

 

It’s a symbiotic relationship! Both are equally important, and in fact are critical to improving Organization’s abilities to protect themselves.

 

You MUST be able to map from one process to another.

 

Cheers

 

Terry MacDonald

Senior STIX Subject Matter Expert

SOLTRA | An FS-ISAC and DTCC Company

+61 (407) 203 206 | terry@soltra.com

 

 

From: cti-stix@lists.oasis-open.org [mailto:cti-stix@lists.oasis-open.org] On Behalf Of Jordan, Bret
Sent: Tuesday, 1 December 2015 4:35 AM
To: Jason Keirstead <Jason.Keirstead@ca.ibm.com>
Cc: Richard Struse <Richard.Struse@HQ.DHS.GOV>; cti-stix@lists.oasis-open.org; Wunder, John A. <jwunder@mitre.org>
Subject: Re: [cti-stix] STIX: Messaging Standard vs. Document Standard

 

I agree with Jason.  

 

Thanks,

 

Bret

 

 

 

Bret Jordan CISSP

Director of Security Architecture and Standards | Office of the CTO

Blue Coat Systems

PGP Fingerprint: 63B4 FC53 680A 6B7D 1447  F2C0 74F8 ACAE 7415 0050

"Without cryptography vihv vivc ce xhrnrw, however, the only thing that can not be unscrambled is an egg." 

 

On Nov 30, 2015, at 08:35, Jason Keirstead <Jason.Keirstead@ca.ibm.com> wrote:

 

Precisely.

If we can agree on the below.. then work on the standardization of messages can be done independently of the underlying model.

RE @Sean: However, I do not view these message specifications as an alternative or independent thing from the model/ontology. I would view them as a layer on top of the model/ontology that allows focused and explicit representation of a small subset of information from the model/ontology that is relevant for a given exchange use case.

I disagree here - this is why we are having such a hard time with the current paradigm.

There is no actual reason that indicator or sighting messages need to be a layer on top of the ontology. They are for totally different use cases and can be developed completely independently.

-
Jason Keirstead
Product Architect, Security Intelligence, IBM Security Systems
www.ibm.com/security | www.securityintelligence.com

Without data, all you are is just another person with an opinion - Unknown


<graycol.gif>"Struse, Richard" ---11/30/2015 11:04:55 AM---So, what I think I’m hearing is that we envision a world where we define a serialization for STIX &

From: "Struse, Richard" <Richard.Struse@HQ.DHS.GOV>
To: Jason Keirstead/CanEast/IBM@IBMCA, "Wunder, John A." <jwunder@mitre.org>
Cc: "cti-stix@lists.oasis-open.org" <cti-stix@lists.oasis-open.org>
Date: 11/30/2015 11:04 AM
Subject: RE: [cti-stix] STIX: Messaging Standard vs. Document Standard





So, what I think I’m hearing is that we envision a world where we define a serialization for STIX & CybOX (let’s assume in JSON) and implementations can exchange “documents” using the serialization of the complete data model (e.g. for communicating a new TTP for an existing threat actor).  However, in addition to this, we might define/standardized specialized message exchanges for a set of common use-cases such as indicator or indicator-sighting exchange.  This would allow appliances, for example, to simply implement the use-case-specific message exchanges that make sense without having to implement the full STIX model.

As a result, I foresee implementations asserting what exchanges they support, perhaps as follows:

CTI-O-MATIC Threat Analysis Platform
                STIX Exchange: SUPPPORTED
                Indicator Exchange: SUPPORTED
                Indicator-Sighting Exchange: SUPPORTED
                Etc.

ACME IDS 9000 Appliance
                STIX Exchange:  NOT SUPPORTED
                Indicator Exchange: SUPPORTED
                Indicator-Sighting Exchange: SUPPORTED


Does this make sense?
From: cti-stix@lists.oasis-open.org [mailto:cti-stix@lists.oasis-open.org] On Behalf Of Jason Keirstead
Sent:
Monday, November 30, 2015 9:47 AM
To:
Wunder, John A.
Cc:
cti-stix@lists.oasis-open.org
Subject:
Re: [cti-stix] STIX: Messaging Standard vs. Document Standard

"What about a new TTP for an existing threat actor? I would not want to have to do an RDF-based exchange to share that type of information (still holding out hope for a reasonable JSON-LD approach) but I’m also not sure we can build messages to cover those use cases."

I believe you would indeed do a complex exchange for that. This is not a "messaging" use case, it is a "document share" use case. The difference in complexity between sharing TTP information to sighting information is similar to emailing a word document vs. engaging in an IM session. It's not the same.

My point is that the huge amount of third party vendors who want to "speak STIX" to communicate and/or absorb indicators, observables, and sightings, are not interested in use cases like "TTP for an existing threat actor". They don't have that information, and they can't act on that information. You aren't going to get TTP information out of an IPS, and you aren't going to send TTP information to an IDS or Firewall. But you will get Indicators and sightings from an IPS, and you will want to send observables to an IDS or Firewall.

These are the two different use cases - one that lends itself to a semantic model, and one that lends itself to a compact and coherent messaging format.

-
Jason Keirstead
Product Architect, Security Intelligence, IBM Security Systems
www.ibm.com/security | www.securityintelligence.com

Without data, all you are is just another person with an opinion - Unknown


<graycol.gif>"Wunder, John A." ---11/30/2015 10:04:36 AM---So to be honest I’m not yet as convinced on this approach as all of you (sorry). I can definitely se

From:
"Wunder, John A." <jwunder@mitre.org>
To:
"cti-stix@lists.oasis-open.org" <cti-stix@lists.oasis-open.org>
Date:
11/30/2015 10:04 AM
Subject:
Re: [cti-stix] STIX: Messaging Standard vs. Document Standard
Sent by:
<cti-stix@lists.oasis-open.org>






So to be honest I’m not yet as convinced on this approach as all of you (sorry). I can definitely see the value of messages at the level of sightings and indicators but it seems to me like there’s a giant middle ground of use cases where we don’t want to define tightly-scoped messages but the document-based approach would still be a burden. For these cases I was hoping the JSON serialization of the full model would be used.


For example, would we have a message to represent a new incident? What would the message semantics be? What about a new TTP for an existing threat actor? I would not want to have to do an RDF-based exchange to share that type of information (still holding out hope for a reasonable JSON-LD approach) but I’m also not sure we can build messages to cover those use cases.


Jason, Jon, Mark…what do you all think about that? Would we define messages for that? Would we have third-party messages (i.e. my app can define a non-standard CTI message based on the data model)? Would we just use RDF?


John

On Nov 30, 2015, at 8:42 AM, Jason Keirstead <Jason.Keirstead@CA.IBM.COM> wrote:

+1 to all below recommendations... exactly my line of thinking.

It may or may not be more work to undertake these two parallel efforts - but I believe that it would allow both efforts to more forward in a faster and more coherent way than the current methodology.

-
Jason Keirstead
Product Architect, Security Intelligence, IBM Security Systems

www.ibm.com/security | www.securityintelligence.com

Without data, all you are is just another person with an opinion - Unknown


<graycol.gif>"Baker, Jon" ---11/30/2015 09:36:44 AM---+1 Thanks for thinking through the underlying issues that might be making it so hard to achieve cons


From:
"Baker, Jon" <bakerj@mitre.org>
To:
Jason Keirstead/CanEast/IBM@IBMCA, "
cti-stix@lists.oasis-open.org" <cti-stix@lists.oasis-open.org>
Date:
11/30/2015 09:36 AM
Subject:
RE: [cti-stix] STIX: Messaging Standard vs. Document Standard
Sent by:
<
cti-stix@lists.oasis-open.org>






+1

Thanks for thinking through the underlying issues that might be making it so hard to achieve consensus. I completely agree that by trying to develop a messaging standard and a document standard in one effort is a significant source of frustration for this group. This is how I have thought about this issue:



STIX has two primary use cases

UC1: Holistic cyber threat analysis
UC2: Exchange cyber threat information

Requirements for UC1 are not always conducive to effective information exchange

My basic recommendation would be as follows:

Differentiate analysis and sharing requirements

avoid overloading analysis model with exchange requirements
avoid overloading exchange with analysis requirements

Develop a high level model of cyber threat intelligence for analysis

initially in UML, but a semantic representation can be developed

Develop messages tailored to information exchange needs

each exchange has a formal specification
ensure messages are compatible with the analysis model
allow protocol and serialization to be dictated by information exchange needs
initially specify only a few well known and well defined messages
plan for many messages, but add messages over time as real needs are understood


Thanks,

Jon

============================================
Jonathan O. Baker
J83D - Cyber Security Partnerships, Sharing, and Automation
The MITRE Corporation
Email:
bakerj@mitre.org

From:
cti-stix@lists.oasis-open.org [mailto:cti-stix@lists.oasis-open.org] On Behalf Of Jason Keirstead
Sent:
Thursday, November 26, 2015 8:47 AM
To:
cti-stix@lists.oasis-open.org
Subject:
[cti-stix] STIX: Messaging Standard vs. Document Standard

When I originally started this message, I had started it with a "here is why I am against JSON-LD" stance, but then decided to take a step FAR BACK and try to figure out / tease apart the fundamental reasons why people are both for and against JSON-LD. As a result of my analysis, I think am starting to figure out why there are two diametrically opposed camps here.

The root I believe is that there is a fundamental disconnect between an ideal messaging standard and a document standard, yet STIX is trying to serve both masters. I am not sure that it can, and keep everyone happy. At any rate, I hope if everyone can read through the below, it will at least help each camp start to see the other's point of view.

Things desired in a document standard:

- Clarity of the source and meaning of the data
- Readability by humans can sometimes be a factor depending on use cases
- Byte-efficiency is a secondary or tertiary concern (disk is cheap)

In a document standard, it is now the standard practice that the schema accompanies the document. This is the core tenant of JSON-LD and other related semantic technologies - that your data is annotated in a way such that it can be linked back to the schema that defined it, which then also allows you to infer the semantic meaning behind fields in the document. This lets people and systems cross-correlate and search documents of different types that contain fields that are related semantically, without having to have standard-specific code written for them.

Things desired in a messaging standard:

- Maximum byte efficiency (bandwidth is not cheap)
- Absolutely zero ambiguity
- Readability by humans is a secondary (or tertiary) concern, sometimes not a concern at all

In a messaging standard, the schema has no reason to accompany the message, because anyone who implements it would have zero ambiguity anyway, and doing so greatly inflates the size of the messages. You also don't have to infer meaning of a field in a messaging standard, because the meaning is fixed and is not open to any interpretation. As such, semantic technologies are not required in a messaging standard, because they aren't even applicable to the use case.

The root of our problem here and I believe why we can not come to consensus, is we are trying to come up with one standard that does both things, which are actually philosophically opposed to each-other. There is an extremely large community of people and systems who want to "speak STIX", but they have no plans to STORE STIX, and this could not care less about semantic representations. Similarly, there is a large community of people and systems who want to (and already have) systems with large STIX warehouses, and very much care about semantic representations, so that they can tie that data to other systems.

Maybe we should take a step back and look at this more critically. If you look at what people care about from a "frequently messaged" perspective (namely of indicators and observable occurrences) maybe that should be moved under TAXII? Currently, TAXII is just a transit protocol and the standard of the messages is simply " a STIX document". I am starting to think that this is not enough and it's part of why we can't reach any consensus. There is no reason that there could not be a messaging format in TAXII to communicate indicators and observables that was an offshoot of STIX but not STIX itself... meanwhile there could continue to be a channel for full/complete "STIX documents" which are transmitted with much less frequency.
-
Jason Keirstead
Product Architect, Security Intelligence, IBM Security Systems

www.ibm.com/security | www.securityintelligence.com

Without data, all you are is just another person with an opinion - Unknown




 



Attachment: smime.p7s
Description: S/MIME cryptographic signature



[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]