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Versions: (draft-banghart-mile-rolie-csirt) 00 01 02 03 04 05 06

MILE Working Group                                           S. Banghart
Internet-Draft                                                      NIST
Intended status: Standards Track                                J. Field
Expires: April 30, 2020                                          Pivotal
                                                        October 28, 2019


                  Definition of ROLIE CSIRT Extension
                     draft-ietf-mile-rolie-csirt-06

Abstract

   This document extends the Resource-Oriented Lightweight Information
   Exchange (ROLIE) core to add the Indicator and Incident information
   types, relevant categories, and related requirements needed to
   support Computer Security Incident Response Team (CSIRT) use cases.
   Additional supporting requirements are also defined that describe the
   use of specific formats and link relations pertaining to the new
   information types.

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 https://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 April 30, 2020.

Copyright Notice

   Copyright (c) 2019 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
   Provisions Relating to IETF Documents
   (https://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



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   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 . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Information-type Extensions . . . . . . . . . . . . . . . . .   4
     3.1.  The "incident" information type . . . . . . . . . . . . .   4
     3.2.  The "indicator" information type  . . . . . . . . . . . .   5
   4.  Data format requirements  . . . . . . . . . . . . . . . . . .   5
     4.1.  Incident Object Description Exchange Format . . . . . . .   6
       4.1.1.  Description . . . . . . . . . . . . . . . . . . . . .   6
       4.1.2.  Requirements  . . . . . . . . . . . . . . . . . . . .   6
     4.2.  Structured Threat Information eXpression (STIX) Format  .   6
       4.2.1.  Description . . . . . . . . . . . . . . . . . . . . .   7
       4.2.2.  Requirements  . . . . . . . . . . . . . . . . . . . .   7
     4.3.  Malware Information Sharing Platform (MISP) Format  . . .   7
       4.3.1.  Creating MISP Event Entries . . . . . . . . . . . . .   8
       4.3.2.  MISP Feeds and Manifests  . . . . . . . . . . . . . .   8
   5.  atom:link Extensions  . . . . . . . . . . . . . . . . . . . .   9
     5.1.  Link relations for the 'incident'
           information-type  . . . . . . . . . . . . . . . . . . . .   9
     5.2.  Link relations for the 'indicator'
           information-type  . . . . . . . . . . . . . . . . . . . .  10
     5.3.  Link relations for both information-types . . . . . . . .  10
   6.  atom:category Extensions  . . . . . . . . . . . . . . . . . .  11
     6.1.  Newly registered category values  . . . . . . . . . . . .  11
     6.2.  Expectation and Impact Classes  . . . . . . . . . . . . .  11
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
     7.1.  information-type registrations  . . . . . . . . . . . . .  12
       7.1.1.  incident information-type . . . . . . . . . . . . . .  12
       7.1.2.  indicator information-type  . . . . . . . . . . . . .  12
     7.2.  atom:category scheme registrations  . . . . . . . . . . .  12
       7.2.1.  category:csirt:iodef:purpose  . . . . . . . . . . . .  13
       7.2.2.  category:csirt:iodef:restriction  . . . . . . . . . .  13
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  Examples of Use  . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16








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1.  Introduction

   Threats to computer security are evolving ever more rapidly as time
   goes on.  As software increases in complexity, the number of
   vulnerabilities in systems and networks can increase exponentially.
   Threat actors looking to exploit these vulnerabilities are making
   more frequent and more widely distributed attacks across a large
   variety of systems.  The adoption of liberal information sharing
   amongst attackers allows a discovered vulnerability to be shared and
   used to attack a vulnerable system within a narrow window of time.
   As the skills and knowledge required to identify and combat these
   attacks become more and more specialized, even a well established and
   secure system may find itself unable to quickly respond to an
   incident.  Effective identification of and response to a
   sophisticated attack requires open cooperation and collaboration
   between defending operators, software vendors, and end-users.  To
   improve the timeliness of responses, automation must be used to
   acquire, contextualize, and put to use shared computer security
   information.

   Computer Security Incident Response Teams (CSIRTs) share two primary
   forms of information: incidents and indicators.  Using these forms of
   information, analysts are able to perform a wide range of activities
   both proactive and reactive to improve the security of their systems.

   Incident information describes a cyber security incident.  Such
   information may include attack characteristics, information about the
   attacker, and attack vector data.  Sharing this information helps
   analysts within the sharing community to inoculate their systems
   against similar attacks, providing proactive protection.

   Indicator information describes the symptoms or necessary pre-
   conditions of an attack.  Everything from system vulnerabilities to
   unexpected network traffic can help analysts secure systems and
   prepare for an attack.  Making this information available for sharing
   aids in the proactive defense of systems both within an operating
   unit but also for any CSIRTs that are part of a sharing consortium.

   As a means to bring automation of content discovery and dissemination
   into the CSIRT domain, this specification provides an extension to
   the Resource-Oriented Lightweight Information Exchange (ROLIE) core
   [RFC8322] designed to address CSIRT use cases.  The primary purpose
   of this extension is to define two new information types: incident,
   and indicator, along with formats and link relations that support
   these information-types.






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2.  Terminology

   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 [RFC8174].

   Definitions for some of the common computer security-related
   terminology used in this document can be found in Section 2 of
   [RFC5070].

   As an extension of [RFC8322], this document refers to many terms
   defined in that document.  In particular, the use of "Entry" and
   "Feed" are aligned with the definitions presented there.

   Several places in this document refer to the "information-type" of a
   Resource (Entry or Feed).  This refers to the "term" attribute of an
   "atom:category" element whose scheme is
   "urn:ietf:params:rolie:category:information-type".  For an Entry,
   this value can be inherited from it's containing Feed as per
   [RFC8322].

3.  Information-type Extensions

3.1.  The "incident" information type

   When an "atom:category" element has a "scheme" attribute equal to
   "urn:ietf:params:rolie:category:information-type", the "term"
   attribute defines the information type of the associated resource.  A
   new valid "term" value for this "scheme": "incident", is described in
   this section, and registered in Section 7.1.1.

   The "incident" information type represents any information describing
   or pertaining to a computer security incident.  This document uses
   the definition of incident provided by [RFC4949].  Provided below is
   a non-exhaustive list of information that may be considered to be an
   incident information type.

   o  Timing information: start and end times for the incident and/or
      the response.

   o  Descriptive information: plain text or machine readable data that
      provides some degree of description of the incident itself.

   o  Response information: the methods and results of a response to the
      incident.

   o  Meta and contact information: data about the CSIRT that recorded
      the information, or the operator that enacted the response.



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   o  Effect and result information: data that describes the effects of
      an incident, or what the final results of the incident are.

   Note again that this list is not exhaustive, any information that is
   in the abstract realm of an incident should be classified under this
   information-type.

3.2.  The "indicator" information type

   When an "atom:category" element has a "scheme" attribute equal to
   "urn:ietf:params:rolie:category:information-type", the "term"
   attribute defines the information type of the associated resource.  A
   new valid "term" value for this "scheme": "indicator", is described
   in this section, and registered in Section 7.1.2.

   The "indicator" information type represents computer security
   indicators or any information surrounding them.  This document uses
   the definition of indicator provided by [RFC4949].  Some examples of
   indicator information are provided below, but note that indicator is
   defined in an abstract sense, to be understood as a flexible and
   widely-applicable definition.

   o  Specific vulnerabilities that indicate a vector for attack.

   o  Signs of malicious reconnaissance.

   o  Definitions of patterns of other indicators.

   o  Events that may indicate an attack and information regarding those
      events.

   o  Meta information about the collecting agent.

   This list is intended to provide examples of the indicator
   information-type, not to define it.

4.  Data format requirements

   This section defines usage guidance and additional requirements
   related to data formats above and beyond those specified in
   [RFC8322].  The following formats are expected to be commonly used to
   express software descriptor information.  For this reason, this
   document specifies additional requirements to ensure
   interoperability.







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4.1.  Incident Object Description Exchange Format

4.1.1.  Description

   The Incident Object Description Exchange Format (IODEF) is a format
   for representing computer security information commonly exchanged
   between Computer Security Incident Response Teams (CSIRTs) or other
   operational security teams.

   IODEF conveys indicators, incident reports, response activities, and
   related meta-data in an XML serialization.  This information is
   formally structured in order to support and encourage automated
   machine-to-machine security communication, as well as enhanced
   processing at the endpoint.

   The full IODEF specification [RFC7970] provides further high-level
   discussion and technical details.

4.1.2.  Requirements

   For an Entry to be considered as a "IODEF Entry", it MUST fulfill the
   following conditions:

   o  The information-type of the Entry is "indicator" or "incident".
      For a typical Entry, this is derived from the information type of
      the Feed it is contained in.  For a standalone Entry, this is
      provided by an "atom:category" element.

   o  The document linked to by the "href" attribute of the
      "atom:content" element is an IODEF document as per [RFC7970]

   A "IODEF Entry" MUST conform to the following requirements:

   o  The value of the "type" attribute of the "atom:content" element
      MUST be "application/xml".

   o  There MUST be at least one "rolie:property" with the "name"
      attribute equal to "urn:ietf:params:rolie:property:content-id" and
      the "value" attribute exactly equal to the "<Indicator-ID>" or the
      "<Incident-ID>" element in the attached IODEF document.  This
      allows for ROLIE consumers to more easily search for IODEF
      documents without needing to download the document itself.

4.2.  Structured Threat Information eXpression (STIX) Format







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4.2.1.  Description

   STIX is a structured language for describing a wide range of security
   resources.  STIX approaches the problem with a focus on flexibility,
   automation, readability, and extensibility.

   The full STIX specification [stix2] provides further high-level
   discussion and technical details.

4.2.2.  Requirements

   For an Entry to be considered as a "STIX Entry", it MUST fulfill the
   following conditions:

   o  The information-type of the Entry is "indicator" or "incident".
      For a typical Entry, this is derived from the information type of
      the Feed it is contained in.  For a standalone Entry, this is
      provided by an "atom:category" element.

   o  The document linked to by the "href" attribute of the
      "atom:content" element is a STIX object as per [stix2]

   A "STIX Entry" MUST conform to the following requirements:

   o  The value of the "type" attribute of the "atom:content" element
      MUST be "application/xml" or "application/json".

   o  There MUST be at least one "rolie:property" with the "name"
      attribute equal to "urn:ietf:params:rolie:property:content-id" and
      the "value" attribute exactly equal to the "<id>" element in the
      attached STIX object . This allows for ROLIE consumers to more
      easily search for STIX objects without needing to download the
      document itself.

4.3.  Malware Information Sharing Platform (MISP) Format

   MISP involves documentation, utilities, and formats designed to
   facilitate the day-to-day duties of security operators.  MISP
   includes it's own data format that is used to share between MISP
   features.  While MISP has Feed features that can share and distribute
   events, it has support for linking to other sharing methods like
   ROLIE.

   MISP is defined by a family of internet drafts currently being
   developed in the IETF.  With that in mind, this extension will
   provide non-normative guidance on using MISP format data in ROLIE.
   In the future, when the MISP format is formally published, this




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   document will be updated to normative requirements around MISP
   content.

4.3.1.  Creating MISP Event Entries

   MISP content should be syndicated in ROLIE using the following
   guidance:

   o  The information-type of the Entry is "indicator".  For a typical
      Entry, this is derived from the information type of the Feed it is
      contained in.  For a standalone Entry, this is provided by an
      "atom:category" element.

   o  The document linked to by the "href" attribute of the
      "atom:content" element is a MISP Event object as per
      [I-D.dulaunoy-misp-core-format]

   o  The value of the "type" attribute of the "atom:content" element
      should be "application/xml".

   o  There should be at least one "rolie:property" with the "name"
      attribute equal to "urn:ietf:params:rolie:property:content-id" and
      the "value" attribute exactly equal to the "<uuid>" element in the
      attached MISP Event.  This allows for ROLIE consumers to more
      easily search for MISP Events without needing to download the
      document itself.

   o  It is also recommended to expose information in the ROLIE Entry
      that is required and recommended to expose in the MISP Manifest
      format.  This ensures better compatibility between a ROLIE Feed
      and a MISP Manifest.

      *  The following fields are required by the MISP draft: info,
         Orgc, timestamp, date

      *  The following fields are recommended by the MISP draft:
         analysis, threat_level_id

4.3.2.  MISP Feeds and Manifests

   MISP Feeds are hosted lists of MISP events, each event represented by
   its UUID.  Users request Events on a one-by-one basis and are served
   the full Event on each request.

   MISP Manifest files list MISP events by their UUIDs as well, but
   provide a variety of metadata for each Event inline.  After examining
   the minimized and stripped Event in the manifest, a user could search




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   for the Event UUID of interest in a locally located folder of Event
   files where the file name is the UUID of the Event.

   ROLIE hosting MISP data would operate as a combination of these
   approaches.  Each ROLIE Feed would contain a list of Event Entries,
   each with metadata and identifying information about a given Event.
   Should the user be interested in the Event, the Event Entry provides
   a direct link to download the full Event.  In short, a ROLIE MISP
   Feed is minimally mappable to a MISP Manifest file where a resolvable
   link to the MISP Event was injected into each Event described in the
   Manifest.

   With that in mind, a MISP Feed as well as a MISP Manifest with
   attached local file list could be fully converted and hosted as a
   ROLIE repository.  As a lower overhead alternative, a ROLIE server
   could simply provide a view into MISP data.

5.  atom:link Extensions

   This section defines additional link relationships that
   implementations MUST support.  These relationships are not registered
   in the Link Relation IANA table as their use case is too narrow.
   Each relationship is named and described.

   These relations come in related pairs.  The first of each pair is
   expected to be more common, as they can be determined at the time
   that the Entry is created.  The second of each pair will often need
   to be added retroactively to an Entry.

5.1.  Link relations for the 'incident' information-type

   If a ROLIE server supports the incident information-type, then these
   link relations MUST be supported.


















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   +------------+------------------------------------------------------+
   | Name       | Description                                          |
   +------------+------------------------------------------------------+
   | indicators | Provides a link to a collection of zero or more      |
   |            | instances of cyber security indicators that are      |
   |            | associated with the resource.                        |
   | evidence   | Provides a link to a collection of zero or more      |
   |            | resources that provides some proof of attribution    |
   |            | for an incident. The evidence may or may not have    |
   |            | any identified chain of custody.                     |
   | attacker   | Provides a link to a collection of zero or more      |
   |            | resources that provides a representation of the      |
   |            | attacker.                                            |
   | vector     | Provides a link to a collection of zero or more      |
   |            | resources that provides a representation of the      |
   |            | method used by the attacker.                         |
   +------------+------------------------------------------------------+

    Table 1: Link Relations for Resource-Oriented Lightweight Indicator
                                 Exchange

5.2.  Link relations for the 'indicator' information-type

   If a ROLIE server supports the indicator information-type, then these
   link relations MUST be supported.

   +-----------+-------------------------------------------------------+
   | Name      | Description                                           |
   +-----------+-------------------------------------------------------+
   | incidents | Provides a link to a collection of zero or more       |
   |           | instances of incident representations associated with |
   |           | the resource.                                         |
   +-----------+-------------------------------------------------------+

    Table 2: Link Relations for Resource-Oriented Lightweight Indicator
                                 Exchange

5.3.  Link relations for both information-types

   If a ROLIE server supports either the incident or the indicator
   information-types, then these link relations MUST be supported.










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   +-----------------------+-------------------------------------------+
   | Name                  | Description                               |
   +-----------------------+-------------------------------------------+
   | assessments           | Provides a link to a collection of zero   |
   |                       | or more resources that represent the      |
   |                       | results of executing a benchmark.         |
   | reports               | Provides a link to a collection of zero   |
   |                       | or more resources that represent RID      |
   |                       | reports.                                  |
   | traceRequests         | Provides a link to a collection of zero   |
   |                       | or more resources that represent RID      |
   |                       | traceRequests.                            |
   | investigationRequests | Provides a link to a collection of zero   |
   |                       | or more resources that represent RID      |
   |                       | investigationRequests.                    |
   +-----------------------+-------------------------------------------+

    Table 3: Link Relations for Resource-Oriented Lightweight Indicator
                                 Exchange

6.  atom:category Extensions

6.1.  Newly registered category values

   This document registers two additional registered atom:category
   names: 'urn:ietf:params:rolie:category:csirt:iodef:purpose' and
   'urn:ietf:params:rolie:category:csirt:iodef:restriction'.  These
   categories expose important information from inside the attached
   IODEF document.  The Purpose and Restriction elements are often used
   to sort or cateogrize IODEF documents, and in some use cases,
   determine the security and access permissions of the document.

   When the name attribute of the category is
   'urn:ietf:params:rolie:category:csirt:iodef:purpose', the value
   attribute SHOULD be constrained as per section 3.2 of IODEF
   [RFC7970], e.g.  traceback, mitigation, reporting, or other.

   When the name attribute of the category is
   'urn:ietf:params:rolie:category:csirt:iodef:restriction', the value
   attribute SHOULD be constrained as per section 3.2 of IODEF
   [RFC7970], e.g.  public, need-to-know, private, default.

6.2.  Expectation and Impact Classes

   It is frequently the case that an organization will need to triage
   their investigation and response activities based upon, e.g., the
   state of the current threat environment, or simply as a result of
   having limited resources.



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   In order to enable operators to effectively prioritize their response
   activity, it is RECOMMENDED that feed implementers provide Atom
   categories that correspond to the IODEF Expectation and Impact
   classes.  The availability of these feed categories will enable
   clients to more easily retrieve and prioritize cyber security
   information that has already been identified as having a specific
   potential impact, or having a specific expectation.

   Support for these categories may also enable efficiencies for
   organizations that already have established (or plan to establish)
   operational processes and workflows that are based on these IODEF
   classes.

7.  IANA Considerations

7.1.  information-type registrations

   IANA has added the following entries to the "ROLIE Security Resource
   Information Type Sub-Registry" registry located at
   <https://www.iana.org/assignments/rolie/category/information-type> .

7.1.1.  incident information-type

   The entry is as follows:

      name: incident

      index: TBD

      reference: This document, Section 3.1

7.1.2.  indicator information-type

   The entry is as follows:

      name: indicator

      index: TBD

      reference: This document, Section 3.2

7.2.  atom:category scheme registrations

   IANA has added the following entries to the "ROLIE URN Parameters"
   registry located in <https://www.iana.org/assignments/rolie/>.






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7.2.1.  category:csirt:iodef:purpose

   The entry is as follows:

      name: category:csirt:iodef:purpose

      Extension IRI: urn:ietf:params:rolie:category:csirt:iodef:purpose

      Reference: This document, Section 6.1

      Subregistry: None

7.2.2.  category:csirt:iodef:restriction

   The entry is as follows:

      name: category:csirt:iodef:restriction

      Extension IRI:
      urn:ietf:params:rolie:category:csirt:iodef:restriction

      Reference: This document, Section 6.1

      Subregistry: None

8.  Security Considerations

   This document implies the use of ROLIE in high-security use cases; as
   such, added care should be taken to fortify and secure ROLIE
   repositories and clients using this extension.  The guidance in the
   ROLIE core specification is strongly recommended, and implementers
   should consider adding additional security measures as they see fit.

   When providing a private workspace for closed sharing, it is
   recommended that the ROLIE repository checks user authorization when
   the user sends a GET request to the service document.  If the user is
   not authorized to send any requests to a given workspace or
   collection, that workspace or collection should be truncated from the
   service document in the response.  In this way the existence of
   unauthorized content remains unknown to potential attackers,
   hopefully reducing attack surface.

   When sharing IODEF Version 2 documents using a ROLIE server, care
   should be taken to seperate IODEF Entries into different workspaces
   based on the "restriction" attribute of the IODEF Document (and
   therefore the restriction property in ROLIE).  Security and access
   controls are most effectively deployed at the workspace level, as




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   such, keeping private and need-to-know IODEF documents in their own
   workspace helps prevent unintended information leakage.

9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC4287]  Nottingham, M., Ed. and R. Sayre, Ed., "The Atom
              Syndication Format", RFC 4287, DOI 10.17487/RFC4287,
              December 2005, <https://www.rfc-editor.org/info/rfc4287>.

   [RFC4949]  Shirey, R., "Internet Security Glossary, Version 2",
              FYI 36, RFC 4949, DOI 10.17487/RFC4949, August 2007,
              <https://www.rfc-editor.org/info/rfc4949>.

   [RFC5023]  Gregorio, J., Ed. and B. de hOra, Ed., "The Atom
              Publishing Protocol", RFC 5023, DOI 10.17487/RFC5023,
              October 2007, <https://www.rfc-editor.org/info/rfc5023>.

   [RFC5070]  Danyliw, R., Meijer, J., and Y. Demchenko, "The Incident
              Object Description Exchange Format", RFC 5070,
              DOI 10.17487/RFC5070, December 2007,
              <https://www.rfc-editor.org/info/rfc5070>.

   [RFC7970]  Danyliw, R., "The Incident Object Description Exchange
              Format Version 2", RFC 7970, DOI 10.17487/RFC7970,
              November 2016, <https://www.rfc-editor.org/info/rfc7970>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8322]  Field, J., Banghart, S., and D. Waltermire, "Resource-
              Oriented Lightweight Information Exchange (ROLIE)",
              RFC 8322, DOI 10.17487/RFC8322, February 2018,
              <https://www.rfc-editor.org/info/rfc8322>.

   [stix2]    Organization for the Advancement of Structured Information
              Standards (OASIS) Cyber Threat Intelligence (CTI)
              Technical Committee, "Structured Threat Information
              Expression 2.0", July 2017, <https://oasis-open.github.io/
              cti-documentation/resources#stix-20-specification>.




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9.2.  Informative References

   [I-D.dulaunoy-misp-core-format]
              Dulaunoy, A. and A. Iklody, "MISP core format", draft-
              dulaunoy-misp-core-format-07 (work in progress), February
              2019.

Appendix A.  Examples of Use

   Use of this extension in a ROLIE repository will not typically change
   that repository's operation.  As such, the general examples provided
   by the ROLIE core document would serve as examples.  Provided below
   is a sample incident ROLIE entry containing an IODEF document:

  <?xml version="1.0" encoding="UTF-8"?>
  <entry xmlns="http://www.w3.org/2005/Atom"
    xmlns:rolie="urn:ietf:params:xml:ns:rolie-1.0">
    <id>f762c77c-057d-45c9-b805-677ab89aaf7c</id>
    <title>Sample Incident</title>
    <published>2018-09-04T18:13:51.0Z</published>
    <updated>2019-08-05T18:13:51.0Z</updated>
    <summary>A document containing an indicator of comprimise. </summary>
    <link rel="self" href="http://www.example.org/rolie/CSIRT/123456"/>
    <link rel="feed" href="http://www.example.org/rolie/CSIRT/"/>
    <rolie:property name=urn:ietf:params:rolie:property:content-id
        value="id847201"/>
    <category
        scheme="urn:ietf:params:rolie:category:information-type"
        term="incident"/>
    <rolie:format
        ns="urn:ietf:params:xml:ns:iodef-2.0"/>
    <content type="application/xml"
        src="http://www.example.org/rolie/csirt/123456/data"/>
  </entry>

   Below is a sample indicator ROLIE entry containing a STIX document:















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   <?xml version="1.0" encoding="UTF-8"?>
   <entry xmlns="http://www.w3.org/2005/Atom"
     xmlns:rolie="urn:ietf:params:xml:ns:rolie-1.0">
     <id>0c99df51-767f-4940-8a09-c4b607b6fe21</id>
     <title>Sample Indicator</title>
     <published>2018-09-04T18:13:51.0Z</published>
     <updated>2019-08-05T18:13:51.0Z</updated>
     <summary>A document containing an incident report. </summary>
     <link rel="self" href="http://www.example.org/rolie/CSIRT/654321"/>
     <link rel="feed" href="http://www.example.org/rolie/CSIRT/"/>
     <rolie:property name=urn:ietf:params:rolie:property:content-id
         value="exmaple:indicator:654321"/>
     <category
         scheme="urn:ietf:params:rolie:category:information-type"
         term="indicator"/>
     <rolie:format
         ns=http://stix.mitre.org/XMLSchema/core/1.2/stix_core.xsd"/>
     <content type="application/xml"
         src="http://www.example.org/rolie/csirt/654321/data"/>
   </entry>

Authors' Addresses

   Stephen A. Banghart
   National Institute of Standards and Technology
   100 Bureau Drive
   Gaithersburg, Maryland
   USA

   Phone: (301)975-4288
   Email: sab3@nist.gov


   John P. Field
   Pivotal Software, Inc.
   625 Avenue of the Americas
   New York, New York
   USA

   Phone: (646)792-5770
   Email: jfield@pivotal.io










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