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Versions: (draft-pkampana-iodef-guidance) 00 01 02 03 04 05 06 07 08 09 10 11 RFC 8274

MILE Working Group                                         P. Kampanakis
Internet-Draft                                             Cisco Systems
Intended status: Informational                               May 1, 2014
Expires: November 2, 2014


                          IODEF Usage Guidance
                     draft-ietf-mile-iodef-guidance-03

Abstract

   The Incident Object Description Exchange Format [RFC5070] defines a
   data representation that provides a framework for sharing information
   commonly exchanged by Computer Security Incident Response Teams
   (CSIRTs) about computer security incidents.  Since the IODEF model
   includes a wealth of available options that can be used to describe a
   security incident or issue, it can be challenging for implementers to
   develop tools that can Leverage IODEF for incident sharing.  This
   document provides guidelines for IODEF implementers.  It will also
   address how common security indicators can be represented in IODEF
   and use-cases of how IODEF is being used so far.The goal of this
   document is to make IODEF's adoption by vendors easier and encourage
   faster and wider adoption of the model by Computer Security Incident
   Response Teams (CSIRTs) around the world.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on November 2, 2014.

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal



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   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Implementation Strategy  . . . . . . . . . . . . . . . . . . .  3
     3.1.  Recommended classes to implement . . . . . . . . . . . . .  4
     3.2.  Decide what IODEF will be used for . . . . . . . . . . . .  4
   4.  IODEF considerations and how to address them . . . . . . . . .  4
     4.1.  Unnecessary Fields . . . . . . . . . . . . . . . . . . . .  4
     4.2.  External References  . . . . . . . . . . . . . . . . . . .  4
     4.3.  Extensions . . . . . . . . . . . . . . . . . . . . . . . .  5
     4.4.  Predicate logic  . . . . . . . . . . . . . . . . . . . . .  5
     4.5.  Predicate Logic for watchlist of indicators  . . . . . . .  6
     4.6.  Indicator identifiers  . . . . . . . . . . . . . . . . . .  8
     4.7.  Restrictions in IODEF  . . . . . . . . . . . . . . . . . .  9
   5.  Current uses of IODEF  . . . . . . . . . . . . . . . . . . . .  9
     5.1.  Anti-Phishing Working Group  . . . . . . . . . . . . . . .  9
     5.2.  Inter-vendor and Service Provider Exercise . . . . . . . .  9
     5.3.  Collective Intelligence Framework  . . . . . . . . . . . . 13
     5.4.  Other  . . . . . . . . . . . . . . . . . . . . . . . . . . 13
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 13
   7.  Updates  . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
   8.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
   9.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     10.1. Normative References . . . . . . . . . . . . . . . . . . . 14
     10.2. Informative References . . . . . . . . . . . . . . . . . . 15
   Appendix A.  Inter-vendor and Service Provider Exercise
                Examples  . . . . . . . . . . . . . . . . . . . . . . 15
     A.1.  Malware  . . . . . . . . . . . . . . . . . . . . . . . . . 15
     A.2.  DDoS . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
     A.3.  Spear-Phishing . . . . . . . . . . . . . . . . . . . . . . 23
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 26








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1.  Introduction

   The Incident Object Description Exchange Format in [RFC5070] defines
   a data representation that provides a framework for sharing
   information commonly exchanged by Computer Security Incident Response
   Teams (CSIRTs) about computer security incidents.  The IODEF data
   model consists of multiple classes and data types that are used in
   the IODEF XML schema.

   The IODEF schema was designed to be able to describe all the possible
   fields that would be needed in a security incident exchange.  Thus,
   IODEF contains plenty data constructs that could potentially make it
   harder for IODEF implementers to decide which are the most important
   ones.  Additionally, in the IODEF schema, there exist multiple fields
   and classes which do not necessarily need to be used in every
   possible data exchange.  Moreover, there are fields that are useful
   only in data exchanges of non-traditional security events.  This
   document tries to address the issues above.  It will also address how
   common security indicators can be represented in IODEF.  It will
   point out the most important IODEF classes for an implementer and
   describe other ones that are not as important.  Also, it addresses
   some common challenges for IODEF implementers and how they should be
   addressed.  The end goal of this document is to make IODEF's adoption
   by vendors easier and encourage faster and wider adoption of the
   model by Computer Security Incident Response Teams (CSIRTs) around
   the world.

   Section 3 discusses the recommended classes and how an IODEF
   implementer should chose the classes to implement.  Section 4
   presents common considerations and implementer will come across and
   how to address them.  Section 5 goes over some basic security
   concepts and how they can be expressed in IODEF.


2.  Terminology

   The terminology used in this document follows the one defined in RFC
   5070 [RFC5070] and I-D.draft-ietf-mile-sci [I-D.ietf-mile-sci].

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].


3.  Implementation Strategy

   It is important for IODEF implementers to be able to distinguish how
   the IODEF classes will be used for incident information exchanges.



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   It is critical for an implementer to follow a strategy according to
   which he will chose to implement various IODEF classes.  It is also
   important to know what the most common classes that will be used to
   describe common security incident or indicators.  Thus, this section
   will describe the most important classes and factors an IODEF
   implementer should take into consideration before designing the
   implementation or tool.

3.1.  Recommended classes to implement

   This section explains the mandatory to implement IODEF classes that
   are required more than once and also are useful.  EventData, Record,
   Assessment, ReportTime, DetectTime, StartTime, ReportTime
   Description, Discovery

   [TODO: More to be added...]

3.2.  Decide what IODEF will be used for

   This section describes that there is no need to implement all fields
   of IODEF, the ones that are necessary for your use-cases.  The
   implementer should look into the schema and decide classes to
   implement (or not) Also it explains that other external schemata
   might be needed to describe incidents or indicators, based on SCI
   draft extensions.

   [TODO: More to be added...]


4.  IODEF considerations and how to address them

4.1.  Unnecessary Fields

   This section talks about fields that do not always play in important
   role like Assessment, Impact

   [TODO: More to be added...]

4.2.  External References

   draft draft-montville-mile-enum-reference-format "This format allows
   the <Version> to be associated with the id rather than the id_type.
   By requiring that a specific type and version be associated with the
   identifier, an implementer can look up the type in an IANA table to
   understand exactly what the identifier in ReferenceName is and how
   s/he may expect that identifier to be structured."

   [TODO: More to be added...]



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4.3.  Extensions

   This section explains how to describe things IODEF can't describe
   ([I-D.ietf-mile-sci] draft), or extensions not yet known, or
   implemented, when do you use another xml schema encapsulated in iodef

   [TODO: More to be added...]

4.4.  Predicate logic

   IODEF [I-D.ietf-mile-rfc5070-bis] allows for nesting of incident
   information.  For example, a EventData Class could include multiple
   Flows or Records.  In turn, a Flow could consist of many Nodes and a
   Record of many RecordData classes.  To ensure consistency, IODEF
   presumes certain predicate logic.

   An EventData class that contains multiple EventData classes depicts
   an Event that consists of smaller events.  For the parent event to
   take place, all the children EventData events SHOULD take place.

   An EventData class with multiple Flows means that all the information
   defined in the flows need to exist for the event described to take
   place.  For Records, the Records in an event just add more context to
   the event, they do not all need to be present for the event to take
   place.  A Record in an EventData class with three RecordData in it,
   means that either of these RecordData classes needs to be present for
   the event described to take place.

   In [RFC5070], if a Flow Class contained two System classes that have
   "source" and "target" as the category attributes, both Systems SHOULD
   be present in order for the Flow to be true and thus marked as an
   event.  There SHOULD NOT be more than one "source" or "watchlist-
   source" and one "target" or "watchlist-target" Systems per Flow.

   In Node class, Node information grouped together under a System class
   depicts different representations of the same System.  For example,
   if a System consists of different Nodes with an IPv4 address, a
   domain-name and an IPv6 address, they all represent the same system.
   Of course, different representations could also be grouped under the
   same Node class.

   [I-D.ietf-mile-rfc5070-bis] defined the HashData Class that describes
   a file's hash information as also described in [RFC5901].  Similar to
   the Node, if a HashData class consists of many digital signatures,
   the signatures represent alternative hash algorithms for the same
   signature.  For example, if the HashData type is file-hash, then the
   signatures represent MD5, SHA1, SHA2 etc hashes.




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   For grouped Key classes the logic changes.  Multiple Key classes in a
   WindowsRegistryKeysModified class represent necessary Windows
   Registry Keys that constitute an indicator.  All SHOULD be present in
   order for the indicator to be present.  Multiple
   WindowsRegistryKeysModified classes grouped under the same RecordData
   class represent alternatives for the same indicator.  For example, if
   a RecordData class included two WindowsRegistryKeysModified classes,
   if either of the classes was true the RecordData class would be true.

4.5.  Predicate Logic for watchlist of indicators

   Multiple indicators occasionally need to be combined in an IODEF
   document.  For example, a botnet might have multiple command and
   control servers.  A consistent predicate logic for indicators SHOULD
   be followed in order to present such relationships in IODEF.

   [I-D.ietf-mile-rfc5070-bis] defines two new category attributes in
   the System Class that can enhance the IODEF predicate logic
   functionality.  These are watchlist-source and watchlist-target and
   they serve for watchlist indicator groupings.  A watchlist of Systems
   means that the information is ORed with the information in the Flow
   section.  In other words, if a Flow Class consists of multiple
   Systems with watchlist-source or watchlist-target attributes the
   Systems of the same watchlist type are ORed in the Flow Class.
   Multiple Flows in the EventData Class follow AND logic.  There SHOULD
   NOT be more than one "watchlist-source" and one "watchlist-target"
   Systems per Flow.  In the following example the EventData class will
   evaluates as a Flow of one System with source address being
   (10.10.10.104 OR 10.10.10.106) AND target address 10.1.1.1






















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   <!-- ...XML code omitted... -->
   <iodef:EventData>
      <iodef:Flow>
         <iodef:System category="watchlist-source" spoofed="no">
            <iodef:Node>
               <iodef:Address category="ipv4-addr">
                  10.10.10.104
               </iodef:Address>
            </iodef:Node>
            <iodef:Node>
               <iodef:Address category="ipv4-addr">
                  10.10.10.106
               </iodef:Address>
            </iodef:Node>
         </iodef:System>
         <iodef:System category="target">
            <iodef:Node>
               <iodef:Address category="ipv4-addr">
                  10.1.1.1
               </iodef:Address>
            </iodef:Node>
         </iodef:System>
      </iodef:Flow>
   </iodef:EventData>
   <!-- ...XML code omitted... -->

   Similarly, the HashData Class includes a type attribute that
   introduces watchlist groupings (i.e.  PKI_email_ds_watchlist,
   PGP_email_ds_watchlist, file_hash_watchlist, email_hash_watchlist).
   Two HashData classes that contain a watchlist type attribute follow
   OR logic in a RecordData class.  In the following example the
   RecordData class consists of either of the two files with two
   different hashes.


















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   <!-- ...XML code omitted... -->
   <iodef:RecordData>
      <iodef:HashData type="file-hash-watchlist">
         <iodef:FileName>dummy.txt</iodef:FileName>
         <ds:Reference>
            <ds:DigestMethod Algorithm=
              "http://www.w3.org/2001/04/xmlenc#sha256"/>
            <ds:DigestValue>
              141accec23e7e5157de60853cb1e01bc38042d
              08f9086040815300b7fe75c184
            </ds:DigestValue>
         </ds:Reference>
      </iodef:HashData>
      <iodef:HashData type="file-hash-watchlist">
         <iodef:FileName>dummy2.txt</iodef:FileName>
         <ds:Reference>
            <ds:DigestMethod Algorithm=
             "http://www.w3.org/2001/04/xmlenc#sha256"/>
            <ds:DigestValue>
              141accec23e7e5157de60853cb1e01bc38042d
              08f9086040815300b7fe75c184
            </ds:DigestValue>
         </ds:Reference>
      </iodef:HashData>
   </iodef:RecordData>
   <!-- ...XML code omitted... -->

   Similarly, [I-D.ietf-mile-rfc5070-bis] introduces the
   WindowsRegistryKeyModified Class which consists of Key Classes.  Key
   has an optional type attribute which has watchlist as an option in
   order to include the ability to group Keys.  Multiple Keys of the
   same watchlist of indicators SHOULD be grouped in the same
   WindowsRegistryKeysModified Class.  These Keys follow OR logic.

4.6.  Indicator identifiers

   [I-D.ietf-mile-sci] defines attrbutes indicator-set-id and indicator-
   uid.  These are data elements that are commonly used as indicators.
   They are used in mutliple IODEF classes.  Their purpose is to be able
   to define indicator relationships and reference respectively.  The
   indicator-uid is used as a unique indicator identifier.
   Practitioners MAY use them to establish that a class represents an
   indicator that is different than other IODEF contextual information.

   On the other hand, an IODEF report could contain multiple indicators
   that are part of the same or different indicator group.  For example,
   an IP source address, a target address, that consitute a Flow and a
   RecordData class respectively could be representing indicators of a



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   virous and the traffic it generates.  In such a situation, the
   indicator-set-id for all the classes (Address, RecordData) MUST be
   the same.  Unrelated indicators MUST contain different
   indicator-set-id attributes or no indicator-set-id attributes.

   Similarly,

4.7.  Restrictions in IODEF

   This section describes how Restriction can pose challenges

   [TODO: More to be added...]


5.  Current uses of IODEF

   IODEF is currently used by various organizations in order to
   represent security incidents and share incident and threat
   information between security operations organizations.

5.1.  Anti-Phishing Working Group

   The Anti-Phishing Working Group ([APWG]) is using [RFC5070] to
   represent email phishing information.  [APWG] also uses IODEF to
   aggregate and share Bot and Infected System Alerting and Notification
   System (BISANS) and Cyber Bullying IODEF records.  Special IODEF
   extensions are used in order to mark the sensitivity of the exchanged
   information.  Shared infected system or email phishing records can
   then be used by interested parties in order to provide mitigations.
   [APWG] leverages tools of its eCRISP-X toolkit in order to share and
   report e-Crime IODEF records.

5.2.  Inter-vendor and Service Provider Exercise

   Various vendors organized and executed an exercise where multiple
   threat indicators were exchanged using IODEF.  The transport protocol
   used was RID.  The threat information shared included incidents like
   DDoS attacks.  Malware and Spear-Phishing.  As this was a proof-of-
   concept (PoC) exercise only example information (no real threats)
   were shared as part of the exchanges.











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         ____________                             ____________
         | Vendor X  |                            | Vendor Y  |
         | RID Agent |_______-------------________| RID Agent |
         |___________|       | Internet  |        |___________|
                             -------------

                      ---- RID Report message --->
                      -- carrying IODEF example ->
                      --------- over TLS -------->

                      <----- RID Ack message -----
                      <--- in case of failure ----

                           PoC peering topology

   The figure above shows how RID interactions took place during the
   PoC.  Participating organizations were running RID Agent software on-
   premises.  The RID Agents formed peering relationships with other
   participating organizations.  When Entity X had a new incident to
   exchange it would package it in IODEF and send it to Entity Y over
   TLS in a RID Report message.  In case there was an issue with the
   message, Entity Y would send an RID Acknowledgement message back to
   Entity X which included an application level message to describe the
   issue.  Interoperability between RID agents and the standards,
   [RFC6545] and [RFC6546], was also proven in this exercise.
   Appendix A includes some of the incident IODEF example information
   that was exchanged by the organizations' RID Agents as part of this
   proof-of-concept.

   The first use-case included sharing of Malware Data Related to an
   Incident between CSIRTs.  After Entity X detected an incident, she
   would put data about malware found during the incident in a backend
   system.  Entity X then decided to share the incident information with
   Entity Y about the malware discovered.  This could be a human
   decision or part of an automated process.

   Below are the steps followed for the malware information exchange
   that was taking place:

   (1)  Entity X has a sharing agreement with Entity Y, and has already
        been configured with the IP address of Entity Y's RID Agent

   (2)  Entity X's RID Agent connects to Entity Y's RID Agent, and
        mutual authentication occurs using PKI certificates.







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   (3)  Entity X pushes out a RID Report message which contains
        information about N pieces of discovered malware.  IODEF is used
        in RID to discribe the

        (a)  Hash of malware files

        (b)  Registry settings changed by the malware

        (c)  C&C Information for the malware

   (4)  Entity Y receives RID Report message, sends RID Acknowledgement
        message

   (5)  Entity Y stores the data in a format that makes it possible for
        the back end to know which source the data came from.

   Another use-case was sharing Distributed Denial of Service (DDoS) as
   presented below information: Entity X, a Critical Infrastructure and
   Key Resource (CIKR) company detects that their internet connection is
   saturated with an abnormal amount of traffic.  Further investigation
   determines that this is an actual DDoS attack.  Entity X's computer
   incident response team (CIRT) contacts their ISP and shares
   information with them about the attack traffic characteristics.  In
   addition, Entity X has an information sharing relationship with
   Entity Y. It shares information with Entity Y on characteristics of
   the attack to watch for.  Entitty X's ISP is being overwhelmed by the
   amount of traffic, so it shares attack signatures and IP addresses of
   the most prolific hosts with its adjacent ISPs.

   Below are the steps followed for a DDoS information exchange:

   (1)  Entity X has a sharing agreement with Entity Y, and has already
        been configured with the IP address of Entity Y's RID Agent

   (2)  Entity X's RID Agent connects to Entity Y's RID Agent, and
        mutual authentication occurs using PKI certificates.

   (3)  Entity X pushes out a RID Report message which contains
        information about the DDoS attack.  IODEF is used in RID to
        discribe the

        (a)  Start and Detect dates and times

        (b)  IP Addresses of nodes sending DDoS Traffic







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        (c)  Sharing and Use Restrictions

        (d)  Traffic characteristics (protocols and ports)

        (e)  HTTP User-Agents used

        (f)  IP Addresses of C&C for a botnet

   (4)  Entity Y receives RID Report message, sends RID Acknowledgement
        message

   (5)  Entity Y stores the data in a format that makes it possible for
        the back end to know which source the data came from.

   One more use-case was sharing spear-phishing email information as
   explained in the following scenario: The board members of several
   defense contractors receive an email inviting them to attend a
   conference in San Francisco.  The board members are asked to provide
   their personally identifiable information such as their home address,
   phone number, corporate email, etc in an attached document which came
   with the email.  The board members were also asked to click on a URL
   which would allow them to reach the sign up page for the conference.
   One of the recipients believes the email to be a phishing attempt and
   forwards the email to their corporate CSIRT for analysis.  The CSIRT
   identifies the email as an attempted spear phishing incident and
   distributes the indicators to their sharing partners.

   Below are the steps followed for a spear-phishing information
   exchange between CSIRTs that was part of this PoC.

   (1)  Entity X has a sharing agreement with Entity Y, and has already
        been configured with the IP address of Entity Y's RID Agent

   (2)  Entity X's RID Agent connects to Entity Y's RID Agent, and
        mutual authentication occurs using PKI certificates.

   (3)  Entity X pushes out a RID Report message which contains
        information about the spear-phishing email.  IODEF is used in
        RID to discribe the

        (a)  Attachment details (file Name, hash, size, malware family

        (b)  Target description (IP, domain, NSLookup)

        (c)  Email information (From, Subject, header information, date/
             time, digital signature)





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        (d)  Confidence Score

   (4)  Entity Y receives RID Report message, sends RID Acknowledgement
        message

   (5)  Entity Y stores the data in a format that makes it possible for
        the back end to know which source the data came from.

5.3.  Collective Intelligence Framework

   The Collective Intelligence Framework [CIF] is a cyber threat
   intelligence management system that uses IODEF to combine known
   malicious threat information from multiple sources and use that it to
   identify, detect and mitigate.  The threat intelligence can be IP
   addresses, domains and URLs that are involved in malicious activity.
   IODEF records can be consumed by a CIF standalone client or CIF
   browser plugins that a user can use to make informed decisions about
   threat information.

   Future use-cases of IODEF could be:

   (1)  ISP notifying a national CERT or orgnaization when it identifies
        and acts upon an incident and CERTs notifying ISPs when they are
        aware of incidents.

   (2)  Suspected phishing emails could be shared amongst organizations
        and national agencies.  Automation could validate web content
        that the suspicious emails are pointing to.  Identified
        malicious content linked in a phishing email could then be
        shared using IODEF.  Phishing campains could thus be subverted
        much faster by automating information sharing using IODEF.

5.4.  Other

   IODEF is also used in various projects and products to consume and
   share security information.  Various vendor incident reporting
   products have the ability to consume and export in IODEF format
   [implementations].  Perl and Python modules (XML::IODEF, Iodef::Pb,
   iodeflib) exist in order to parse IODEF documents and their
   extensions.  Additionally, some worldwide CERT organizations are
   already able to use receive incident information in IODEF.


6.  Security Considerations







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7.  Updates

   version -02 updates:

   (1)  Updated the "Logic for watchlist of indications" section to
        clarify the logic based on community feedback.

   (2)  Added "Inter-vendor and Service Provider Exercise" section.

   (3)  Added Appendix to include actual use-case IODEF examples.

   version -03 updates:

   (1)  Added "Updates" section.

   (2)  Added details about the flow of information exchanges in "Inter-
        vendor and Service Provider Exercise" section.  Also updated the
        usecases with more background information.

   (3)  Added future use-cases in the "Collective Intelligence
        Framework" section

   (4)  Updated Perl and Python references with the actual module names.
        Added IODEF implementation reference "implementations".

   (5)  Added Predicate logic section

   (6)  Updated Logic of watchlist of indicators section to simplify the
        logic and include examples.

   (7)  Renamed Externally defined indicators section to Indicator
        reference and elaborated on the use of indicator-uid and
        indicator-set-uid attribute use.


8.  Acknowledgements


9.  Security Considerations


10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.




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   [RFC5070]  Danyliw, R., Meijer, J., and Y. Demchenko, "The Incident
              Object Description Exchange Format", RFC 5070,
              December 2007.

   [RFC5901]  Cain, P. and D. Jevans, "Extensions to the IODEF-Document
              Class for Reporting Phishing", RFC 5901, July 2010.

   [RFC6545]  Moriarty, K., "Real-time Inter-network Defense (RID)",
              RFC 6545, April 2012.

   [RFC6546]  Trammell, B., "Transport of Real-time Inter-network
              Defense (RID) Messages over HTTP/TLS", RFC 6546,
              April 2012.

10.2.  Informative References

   [APWG]     "APWG", <http://apwg.org/>.

   [CIF]      "CIF", <https://code.google.com/p/
              collective-intelligence-framework/wiki/WhatisCIF>.

   [I-D.ietf-mile-rfc5070-bis]
              Danyliw, R. and P. Stoecker, "The Incident Object
              Description Exchange Format",
              draft-ietf-mile-rfc5070-bis-00 (work in progress),
              May 2013.

   [I-D.ietf-mile-sci]
              Takahashi, T., Landfield, K., Millar, T., and Y.
              Kadobayashi, "IODEF-extension for structured cybersecurity
              information", draft-ietf-mile-sci-13 (work in progress),
              January 2014.

   [implementations]
              "Implementations on IODEF",
              <http://siis.realmv6.org/implementations/>.


Appendix A.  Inter-vendor and Service Provider Exercise Examples

   Below some of the incident IODEF example information that was
   exchanged by the vendors as part of this proof-of-concept Inter-
   vendor and Service Provider Exercise.

A.1.  Malware

   In this test, malware information was exchanged using RID and IODEF.
   The information included file hashes, registry setting changes and



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   the C&C servers the malware uses.

        <?xml version="1.0" encoding="UTF-8"?>
                   <iodef:IODEF-Document xmlns:ds="
                       http://www.w3.org/2000/09/xmldsig#"
                       xmlns:iodef="urn:ietf:params:xml:ns:iodef-1.41">
             <iodef:Incident purpose="reporting">
               <iodef:ReportID name="EXAMPLE CSIRT">
                  189234
               </iodef:ReportID>
               <iodef:ReportTime>
                  2013-03-07T16:14:56.757+05:30
               </iodef:ReportTime>
               <iodef:Description>
                  Malware and related indicators identified
               </iodef:Description>
               <iodef:Assessment occurrence="potential">
                 <iodef:Impact severity="medium" type="info-leak">
                    Malware with Command and Control Server
                    and System Changes
                 </iodef:Impact>
               </iodef:Assessment>
               <iodef:Contact role="creator" type="organization">
                 <iodef:ContactName>EXAMPLE CSIRT</iodef:ContactName>
                 <iodef:Email>emccirt@emc.com</iodef:Email>
               </iodef:Contact>
               <iodef:EventData>
                 <iodef:Method>
                   <iodef:Reference>
                     <iodef:ReferenceName>Zeus</iodef:ReferenceName>
                     <iodef:URL>
                         http://www.threatexpert.com/report.aspx?
                         md5=e2710ceb088dacdcb03678db250742b7
                     </iodef:URL>
                   </iodef:Reference>
                 </iodef:Method>
                 <iodef:Flow>
                   <iodef:System category="watchlist-source">
                     <iodef:Node>
                       <iodef:Address category="ipv4-addr">
                          192.168.2.200
                       </iodef:Address>
                       <iodef:Address category="site-uri">
                          http://zeus.556677889900.com/log-bin/
                          lunch_install.php?aff_id=1&amp;amp;
                          lunch_id=1&amp;amp;maddr=&amp;amp;
                          action=install
                       </iodef:Address>



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                       <iodef:NodeRole attacktype="c2-server"/>
                     </iodef:Node>
                   </iodef:System>
                 </iodef:Flow>
                 <iodef:Record>
                   <iodef:RecordData>
                     <iodef:HashData>
                       <ds:Reference>
                         <ds:DigestMethod Algorithm="
                            http://www.w3.org/2001/04/xmlenc#sha1"/>
                         <ds:DigestValue>
                              MHg2NzUxQTI1MzQ4M0E2N0Q4NkUwRjg0NzYwRj
                              YxRjEwQkJDQzJFREZG</ds:DigestValue>
                       </ds:Reference>
                     </iodef:HashData>
                     <iodef:HashData>
                       <ds:Reference>
                         <ds:DigestMethod Algorithm="
                             http://www.w3.org/2001/04/xmlenc#md5"/>
                         <ds:DigestValue>
                             MHgyRTg4ODA5ODBENjI0NDdFOTc5MEFGQTg5NTE
                             zRjBBNA==
                         </ds:DigestValue>
                       </ds:Reference>
                     </iodef:HashData>
                     <iodef:WindowsRegistryKeysModified>
                       <iodef:Key registryaction="add_value">
                         <iodef:KeyName>
                             HKLM\Software\Microsoft\Windows\
                             CurrentVersion\Run\tamg
                         </iodef:KeyName>
                         <iodef:Value>
                            ?\?\?%System%\wins\mc.exe\?\??
                         </iodef:Value>
                       </iodef:Key>
                       <iodef:Key registryaction="modify_value">
                         <iodef:KeyName>HKLM\Software\Microsoft\
                            Windows\CurrentVersion\Run\dqo
                         </iodef:KeyName>
                         <iodef:Value>"\"\"%Windir%\Resources\
                             Themes\Luna\km.exe\?\?"
                         </iodef:Value>
                       </iodef:Key>
                     </iodef:WindowsRegistryKeysModified>
                   </iodef:RecordData>
                 </iodef:Record>
               </iodef:EventData>
               <iodef:EventData>



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                 <iodef:Method>
                   <iodef:Reference>
                     <iodef:ReferenceName>Cridex</iodef:ReferenceName>
                     <iodef:URL>
                         http://www.threatexpert.com/report.aspx?
                         md5=c3c528c939f9b176c883ae0ce5df0001
                     </iodef:URL>
                   </iodef:Reference>
                 </iodef:Method>
                 <iodef:Flow>
                   <iodef:System category="watchlist-source">
                     <iodef:Node>
                       <iodef:Address category="ipv4-addr">
                          10.10.199.100
                       </iodef:Address>
                       <iodef:NodeRole attacktype="c2-server"/>
                     </iodef:Node>
                     <iodef:Service ip_protocol="6">
                       <iodef:Port>8080</iodef:Port>
                     </iodef:Service>
                   </iodef:System>
                 </iodef:Flow>
                 <iodef:Record>
                   <iodef:RecordData>
                     <iodef:HashData>
                       <ds:Reference>
                         <ds:DigestMethod Algorithm="
                            http://www.w3.org/2001/04/xmlenc#sha1"/>
                         <ds:DigestValue>
                            MHg3MjYzRkUwRDNBMDk1RDU5QzhFMEM4OTVBOUM
                            1ODVFMzQzRTcxNDFD
                         </ds:DigestValue>
                       </ds:Reference>
                       <ds:Reference>
                         <ds:DigestMethod Algorithm="
                            http://www.w3.org/2001/04/xmlenc#md5"/>
                         <ds:DigestValue>MHg0M0NEODUwRkNEQURFNDMzMEE1
                            QkVBNkYxNkVFOTcxQw==</ds:DigestValue>
                       </ds:Reference>
                     </iodef:HashData>
                     <iodef:HashData>
                       <ds:Reference>
                         <ds:DigestMethod Algorithm="
                             http://www.w3.org/2001/04/xmlenc#md5"/>
                         <ds:DigestValue>MHg0M0NEODUwRkNEQURFNDMzMEE
                             1QkVBNkYxNkVFOTcxQw==</ds:DigestValue>
                       </ds:Reference>
                       <ds:Reference>



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                         <ds:DigestMethod Algorithm="http://www.w3.org/
                             2001/04/xmlenc#sha1"/>
                         <ds:DigestValue>MHg3MjYzRkUwRDNBMDk1RDU5QzhFME
                             M4OTVBOUM1ODVFMzQzRTcxNDFD</ds:DigestValue>
                       </ds:Reference>
                     </iodef:HashData>
                     <iodef:WindowsRegistryKeysModified>
                       <iodef:Key registryaction="add_value">
                         <iodef:KeyName>
                            HKLM\Software\Microsoft\Windows\
                            CurrentVersion\Run\KB00121600.exe
                         </iodef:KeyName>
                         <iodef:Value>
                            \?\?%AppData%\KB00121600.exe\?\?
                         </iodef:Value>
                       </iodef:Key>
                     </iodef:WindowsRegistryKeysModified>
                   </iodef:RecordData>
                 </iodef:Record>
               </iodef:EventData>
               <iodef:EventData>
                 <iodef:Expectation action="other"/>
                   <iodef:Flow>
                     <iodef:System category="source"
                           indicator-set-id="91011">
                       <iodef:Node>
                           <iodef:Address category="url"
                              indicator-uid="qrst">
                                 http://foo.com:12345/evil/cc.php
                           </iodef:Address>
                       <iodef:NodeName indicator-uid="rstu">
                           evil.com
                       </iodef:NodeName>
                           <iodef:Address category="ipv4-addr"
                              indicator-uid="stuv">
                                 1.2.3.4</iodef:Address>
                           <iodef:Address category="ipv4-addr"
                              indicator-uid="tuvw">
                                 5.6.7.8 </iodef:Address>
                           <iodef:Address category="ipv6-addr"
                              indicator-uid="uvwx">
                                  2001:dead:beef::</iodef:Address>
                      <iodef:NodeRole category="c2-server"/>
                      </iodef:Node>
                   </iodef:System>
                 </iodef:Flow>
                 <iodef:Record>
                   <iodef:RecordData indicator-set-id="91011">



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                     <iodef:HashData>
                        <ds:Reference>
                           <ds:DigestMethod Algorithm=
                               "http://www.w3.org/2001/04/xmlenc
                                #sha256"/>
                            <ds:DigestValue>
                             141accec23e7e5157de60853cb1e01bc3804
                             2d08f9086040815300b7fe75c184
                            </ds:DigestValue>
                        </ds:Reference>
                       </iodef:HashData>
                     <iodef:WindowsRegistryKeysModified
                       indicator-set-id="91011">
                       <iodef:Key registryaction="add_key"
                       indicator-uid="vwxy">
                         <iodef:KeyName>
                             HKLM\SYSTEM\CurrentControlSet\
                             Services\.Net CLR
                         </iodef:KeyName>
                       </iodef:Key>
                       <iodef:Key registryaction="add_key"
                         indicator-uid="wxyz">
                         <iodef:KeyName>
                             HKLM\SYSTEM\CurrentControlSet\
                             Services\.Net CLR\Parameters
                         </iodef:KeyName>
                         <iodef:Value>
                             \"\"%AppData%\KB00121600.exe\"\"
                         </iodef:Value>
                       </iodef:Key>
                       <iodef:Key registryaction="add_value"
                         indicator-uid="xyza">
                         <iodef:KeyName>
                            HKLM\SYSTEM\CurrentControlSet\Services\
                            .Net CLR\Parameters\ServiceDll
                         </iodef:KeyName>
                         <iodef:Value>C:\bad.exe</iodef:Value>
                       </iodef:Key>
                       <iodef:Key registryaction="modify_value"
                         indicator-uid="zabc">
                         <iodef:KeyName>
                             HKLM\SYSTEM\CurrentControlSet\
                             Services\.Net CLR\Parameters\Bar
                         </iodef:KeyName>
                         <iodef:Value>Baz</iodef:Value>
                       </iodef:Key>
                     </iodef:WindowsRegistryKeysModified>
                   </iodef:RecordData>



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                 </iodef:Record>
               </iodef:EventData>
             </iodef:Incident>
           </iodef:IODEF-Document>

A.2.  DDoS

   The DDoS test exchanged information that described a DDoS including
   protocols and ports, bad IP addresses and HTTP User-Agent fields.
   The IODEF version used for the data representation was based on
   [I-D.ietf-mile-rfc5070-bis]

 <?xml version="1.0" encoding="UTF-8"?>
 <IODEF-Document version="1.00" lang="en"
     xmlns="urn:ietf:params:xml:ns:iodef-1.41"
     xmlns:iodef="urn:ietf:params:xml:ns:iodef-1.41"
     xmlns:iodef-sci="urn:ietf:params:xml:ns:iodef-sci-1.0"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
      <iodef:Incident purpose="reporting" restriction="default">
          <iodef:IncidentID name="csirt.example.com">
              189701
          </iodef:IncidentID>
          <iodef:StartTime>2013-02-05T00:34:45+00:00</iodef:StartTime>
          <iodef:DetectTime>2013-02-05T01:15:45+00:00</iodef:DetectTime>
          <iodef:ReportTime>2013-02-05T01:34:45+00:00</iodef:ReportTime>
          <iodef:description>DDoS Traffic Seen</iodef:description>
             <iodef:Assessment occurrence="actual">
                 <iodef:Impact severity="medium" type="dos">
                 DDoS Traffic</iodef:Impact>
                 <iodef:Confidence rating="numeric">90
                 </iodef:Confidence>
             </iodef:Assessment>
             <iodef:Contact role="creator" type="organization">
                 <iodef:ContactName>Dummy Test</iodef:ContactName>
                 <iodef:Email>contact@dummytest.com</iodef:Email>
             </iodef:Contact>
             <iodef:EventData>
                <iodef:Description>
                    Dummy Test sharing with ISP1
                </iodef:Description>
             <iodef:Expectation action="other"/>
             <iodef:Method>
                <iodef:Reference>
                   <iodef:ReferenceName>
                       Low Orbit Ion Cannon User Agent
                   </iodef:ReferenceName>
                   <iodef:URL>



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                      http://blog.spiderlabs.com/2011/01/loic-ddos-
                      analysis-and-detection.html
                   </iodef:URL>
                   <iodef:URL>
                      http://en.wikipedia.org/wiki/Low_Orbit_Ion_Cannon
                   </iodef:URL>
                </iodef:Reference>
             </iodef:Method>
             <iodef:Flow>
                <iodef:System category="watchlist-source" spoofed="no">
                   <iodef:Node>
                     <iodef:Address category="ipv4-addr">
                        10.10.10.104</iodef:Address>
                   </iodef:Node>
                   <iodef:Node>
                     <iodef:Address category="ipv4-addr">
                        10.10.10.106</iodef:Address>
                                    </iodef:Node>
                   <iodef:Node>
                     <iodef:Address category="ipv4-net">
                      172.16.66.0/24</iodef:Address>
                      </iodef:Node>
                   <iodef:Node>
                     <iodef:Address category="ipv6-addr">
                      2001:db8:dead:beef::</iodef:Address>
                                  </iodef:Node>
    <iodef:Service ip_protocol="6">
       <iodef:Port>1337</iodef:Port>
       <iodef:Application user-agent="Mozilla/5.0 (Macintosh; U;
              Intel Mac OS X 10.5; en-US; rv:1.9.2.12) Gecko/
              20101026 Firefox/3.6.12">
       </iodef:Application>
    </iodef:Service>
               </iodef:System>
                <iodef:System category="target">
                   <iodef:Node>
                     <iodef:Address category="ipv4-addr">
    10.1.1.1</iodef:Address>
                  </iodef:Node>
                  <iodef:Service ip_protocol="6">
                    <iodef:Port>80</iodef:Port>
                  </iodef:Service>
                </iodef:System>
                <iodef:System category="sensor"><iodef:Description>
                    Information provided in FLow class instance is from
                    Inspection of traffic from network tap
                </iodef:Description></iodef:System>
             </iodef:Flow>



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         </iodef:EventData>
     </iodef:Incident>
 </IODEF-Document>

A.3.  Spear-Phishing

   The Spear-Phishing test exchanged information that described a Spear-
   Phishing email including DNS records and addresses about the sender,
   malicious attached file information and email data.  The IODEF
   version used for the data representation was based on
   [I-D.ietf-mile-rfc5070-bis].

 <?xml version="1.0" encoding="UTF-8"?>
 <IODEF-Document version="1.00" lang="en"
     xmlns="urn:ietf:params:xml:ns:iodef-1.41"
     xmlns:iodef="urn:ietf:params:xml:ns:iodef-1.41"
     xmlns:iodef-sci="urn:ietf:params:xml:ns:iodef-sci-1.0"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
      <iodef:Incident purpose="reporting">
          <iodef:IncidentID name="csirt.example.com">
             189601
          </iodef:IncidentID>
          <iodef:StartTime>2013-01-04T08:01:34+00:00</iodef:StartTime>
          <iodef:StopTime>2013-01-04T08:31:27+00:00</iodef:StopTime>
          <iodef:DetectTime>2013-01-04T08:06:12+00:00</iodef:DetectTime>
          <iodef:ReportTime>2013-01-04T09:15:45+00:00</iodef:ReportTime>
          <iodef:description>
             Zeus Spear Phishing E-mail with Malware Attachment
          </iodef:description>
             <iodef:Assessment occurrence="potential">
                 <iodef:Impact severity="medium" type="info-leak">
                 Malware with Command and Control Server and System
                 Changes</iodef:Impact>
             </iodef:Assessment>
             <iodef:Contact role="creator" type="organization">
                 <iodef:ContactName>example.com CSIRT
                 </iodef:ContactName>
                 <iodef:Email>contact@csirt.example.com</iodef:Email>
             </iodef:Contact>
             <iodef:EventData>
               <iodef:Description>Targeting Defense Contractors,
                  specifically board members attending Dummy Con
               </iodef:Description>
             <iodef:Expectation action="other"/>
             <iodef:Method>
                <iodef:Reference indicator_uid="1234">
                   <iodef:ReferenceName>Zeus</iodef:ReferenceName>



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                   </iodef:Reference>
             </iodef:Method>
             <iodef:Flow>
                <iodef:System category="source">
                   <iodef:Node>
                     <iodef:Address category="url">
                           http://www.zeusevil.com</iodef:Address>
                     <iodef:Address category="ipv4-addr">
                           10.10.10.166</iodef:Address>
                    <iodef:Address category="as">
                           225</iodef:Address>
                     <iodef:Address category="ext-value"
                       ext-category="as-name">
                       EXAMPLE-AS - University of Example"
                       </iodef:Address>
                     <iodef:Address category="ext-value"
                       ext-category="as-prefix">
                       172.16..0.0/16
                       </iodef:Address>
                     <iodef:NodeRole category="www"
                       attacktype="malware-distribution"/>
                  </iodef:Node>
               </iodef:System>
             </iodef:Flow>
             <iodef:Flow>
                <iodef:System category="source">
                   <iodef:Node>
                    <iodef:NodeName>mail1.evildave.com</iodef:NodeName>
                     <iodef:Address category="ipv4-addr">
                           172.16.55.6</iodef:Address>
                    <iodef:Address category="asn">
                           225</iodef:Address>
                     <iodef:Address category="ext-value"
                       ext-category="as-name">
                       EXAMPLE-AS - University of Example
                     </iodef:Address>
    <iodef:DomainData>
       <iodef:Name>evildaveexample.com</iodef:Name>
       <iodef:DateDomainWasChecked>2013-01-04T09:10:24+00:00
       </iodef:DateDomainWasChecked>
       <iodef:RelatedDNS RecordType="MX">
           evildaveexample.com MX prefernce = 10, mail exchanger
           = mail1.evildave.com</iodef:RelatedDNS>
       <iodef:RelatedDNS RecordType="A">
           mail1.evildaveexample.com
           internet address = 172.16.55.6</iodef:RelatedDNS>
       <iodef:RelatedDNS RecordType="SPF">
            zuesevil.com. IN TXT \"v=spf1 a mx -all\"



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       </iodef:RelatedDNS>
    </iodef:DomainData>
                  <iodef:NodeRole category="mail"
                        attacktype="spear-phishing"/>
                  </iodef:Node>
                  <iodef:Service>
                     <iodef:EmailInfo>
                        <iodef:Email>emaildave@evildaveexample.com
                        </iodef:Email>
                        <iodef:EmailSubject>Join us at Dummy Con
                        </iodef:EmailSubject>
                        <iodef:X-Mailer>StormRider 4.0
                        </iodef:X-Mailer>
                     </iodef:EmailInfo>
                  </iodef:Service>
               </iodef:System>
               <iodef:System category="target">
                  <iodef:Node>
                     <iodef:Address category="ipv4">
                       192.168.54.2</iodef:Address>
                  </iodef:Node>
                </iodef:System>
             </iodef:Flow>

             <iodef:Record>
               <iodef:RecordData>
                 <iodef:HashData type="file_hash"
                    indicator_uid="1234">
                    <iodef:FileName>Dummy Con Sign Up Sheet.txt
                    </iodef:FileName>
                    <iodef:FileSize>152</iodef:FileSize>
                 <ds:Reference>
                    <ds:DigestMethod Algorithm=
                       "http://www.w3.org/2001/04/xmlenc#sha256"/>
                       <ds:DigestValue>
                         141accec23e7e5157de60853cb1e01bc38042d
                         08f9086040815300b7fe75c184
                       </ds:DigestValue>
                 </ds:Reference>
               </iodef:HashData>
              </iodef:RecordData>
              <iodef:RecordData>
               <iodef:HashData type="PKI_email_ds" valid="0">
                 <ds:Signature>
                  <ds:KeyInfo>
                     <ds:X509Data>
                        <ds:X509IssuerSerial>
                           <ds:X509IssuerName>FakeCA



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                        </ds:X509IssuerName>
                        </ds:X509IssuerSerial>
                        <ds:X509SubjectName>EvilDaveExample
                        </ds:X509SubjectName>
                     </ds:X509Data>
                  </ds:KeyInfo>
                     <ds:SignedInfo>
                      <ds:Reference>
                         <ds:DigestMethod Algorithm=
                           "http://www.w3.org/2001/04/xmlenc#sha256"/>
                         <ds:DigestValue>
                          352bddec13e4e5257ee63854cb1f05de48043d09f9
                          076070845307b7ce76c185
                         </ds:DigestValue>
                     </ds:Reference>
                   </ds:SignedInfo>
                 </ds:Signature>
              </iodef:HashData>
           </iodef:RecordData>
          </iodef:Record>
         </iodef:EventData>
     </iodef:Incident>
 </IODEF-Document>


Author's Address

   Panos Kampanakis
   Cisco Systems
   170 West Tasman Dr.
   San Jose, CA  95134
   US

   Email: pkampana@cisco.com

















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