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% Title = "MISP core format" % abbrev = "MISP core format" % category = "info" % docName = "draft-dulaunoy-misp-core-format" % ipr= "trust200902" % area = "Security" % % date = 2016-10-01T00:00:00Z % % author % initials="A." % surname="Dulaunoy" % fullname="Alexandre Dulaunoy" % abbrev="CIRCL" % organization = "Computer Incident Response Center Luxembourg" % [author.address] % email = "alexandre.dulaunoy@circl.lu" % phone = "+352 247 88444" % [author.address.postal] % street = "41, avenue de la gare" % city = "Luxembourg" % code = "L-1611" % country = "Luxembourg" % author % initials="A." % surname="Iklody" % fullname="Andras Iklody" % abbrev="CIRCL" % organization = "Computer Incident Response Center Luxembourg" % [author.address] % email = "andras.iklody@circl.lu" % phone = "+352 247 88444" % [author.address.postal] % street = "41, avenue de la gare" % city = "Luxembourg" % code = "L-1611" % country = "Luxembourg"
.# Abstract
This document describes the MISP core format used to exchange indicators and threat information between MISP (Malware Information and threat Sharing Platform) instances. The JSON format includes the overall structure along with the semantic associated for each respective key. The format is described to support other implementations which reuse the format and ensuring an interoperability with existing MISP [@?MISP-P] software and other Threat Intelligence Platforms.
{mainmatter}
Introduction
Sharing threat information became a fundamental requirements in the Internet, security and intelligence community at large. Threat information can include indicators of compromise, malicious file indicators, financial fraud indicators or even detailed information about a threat actor. MISP started as an open source project in late 2011 and the MISP format started to be widely used as an exchange format within the community in the past years. The aim of this document is to describe the specification and the MISP core format.
Conventions and 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 RFC 2119 [@!RFC2119].
Format
Overview
The MISP core format is in the JSON [@!RFC4627] format. In MISP, an event is composed of a single JSON object.
A capitalized key (like Event, Org) represent a data model and a non-capitalized key is just an attribute. This nomenclature can support an implementation to represent the MISP format in another data structure.
Event
An event is a simple meta structure scheme where attributes and meta-data are embedded to compose a coherent set of indicators. An event can be composed from an incident, a security analysis report or a specific threat actor analysis. The meaning of an event only depends of the information embedded in the event.
Event Attributes
uuid
uuid represents the Universally Unique IDentifier (UUID) [@!RFC4122] of the event. The uuid MUST be preserved for any updates or transfer of the same event. UUID version 4 is RECOMMENDED when assigning it to a new event.
uuid is represented as a JSON string. uuid MUST be present.
id
id represents the human-readable identifier associated to the event for a specific MISP instance.
id is represented as a JSON string. id SHALL be present.
published
published represents the event publication state. If the event was published, the published value MUST be true. In any other publication state, the published value MUST be false.
published is represented as a JSON boolean. published MUST be present.
info
info represents the information field of the event. info a free-text value to provide a human-readable summary of the event. info SHOULD NOT be bigger than 256 characters.
info is represented as a JSON string. info MUST be present.
threat_level_id
threat_level_id represents the threat level.
- 0:
- Undefined
- 1:
- Low
- 2:
- Medium
- 3:
- High
If a higher granularity is required, a MISP taxonomy applied as a Tag SHOULD be preferred.
threat_level_id is represented as a JSON string. threat_level_id SHALL be present.
date
date represents a reference date to the event in ISO 8601 format (date only: YYYY-MM-DD). This date corresponds to the date the event occured, which may be in the past.
date is represented as a JSON string.
timestamp
timestamp represents a reference time when the event was created, or last updated. timestamp is expressed in seconds (decimal) since 1st of January 1970 (Unix timestamp). The time zone MUST be UTC.
timestamp is represented as a JSON string. timestamp MUST be present.
publish_timestamp
publish_timestamp represents a reference time when the event was published. published_timestamp is expressed in seconds (decimal) since 1st of January 1970 (Unix timestamp). At each publication of an event, publish_timestamp MUST be updated. The time zone MUST be UTC.
publish_timestamp is represented as a JSON string. publish_timestamp MUST be present.
org_id
org_id represents the Universally Unique IDentifier (UUID) [@!RFC4122] of the organization which generated the event. The org_id MUST be updated when the event is generated by a new instance.
org_id is represented as a JSON string. org_id MUST be present.
orgc_id
orgc_id represents the Universally Unique IDentifier (UUID) [@!RFC4122] of the organization which created the event. The orgc_id MUST be preserved for any updates or transfer of the same event. UUID version 4 is RECOMMENDED when assigning it to a new event. orgc_id is globally assigned to an organization and SHALL be kept overtime.
orgc_id is represented as a JSON string. orgc_id MUST be present.
attribute_count
attribute_count represents the number of attributes in the event. attribute_count is expressed in decimal.
attribute_count is represented as a JSON string. attribute_count SHALL be present.
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Acknowledgements
The authors wish to thank all the MISP community to support the creation of open standards in threat intelligence sharing.