Network Working Group A. Dulaunoy Internet-Draft P. Bourmeau Expires: December 11, 2020 CIRCL June 9, 2020 Recommendations on naming threat actors Abstract This document provides advice on the naming of threat actors (also known as malicious actors). The objective is to provide practical advices for organisations such as security vendors or organisations attributing incidents to a group of threat actor. It also discusses the implication of naming a threat actor towards intelligence analysts and threat intelligence platforms such as MISP [MISP-P]]. 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/. 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Dulaunoy & Bourmeau Expires December 11, 2020 [Page 1] Internet-Draft Recommendations on naming threat actors June 2020 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Conventions and Terminology . . . . . . . . . . . . . . . 3 2. Recommendations . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Reusing threat actor naming . . . . . . . . . . . . . . . 3 2.2. Uniqueness . . . . . . . . . . . . . . . . . . . . . . . 3 2.3. Format . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.4. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 4 2.5. Don't confuse actor naming with malware naming . . . . . 4 2.6. Directory . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 4 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7.1. Normative References . . . . . . . . . . . . . . . . . . 5 7.2. Informative References . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction In threat intelligence, a name can be assigned to a threat actor without specific guidelines. This leads to issues such as a: o A proliferation of threat actor names generating overlaps or different names for similar threat actors (e.g. some threat actors have more than 10 synonyms) o Ambiguity in the words used to name the threat actor in different contexts (e.g. using common words) o No clearly defined text format to describe the same threat actor (e.g. Is the threat actor name case sensitive? Is there a dash or a space between the two words?) o Confusion between techniques/tools used by a threat actor versus its name (e.g. naming a threat actor after a specific malware used) o Lack of source and list from vendors to describe their threat actor names and the reasoning behind the naming (e.g. did they name the threat actor after a specific set of campaigns? or specific set of targets?) o Lack of time-based information about the threat actor name, such as date of naming or and UUID. Dulaunoy & Bourmeau Expires December 11, 2020 [Page 2] Internet-Draft Recommendations on naming threat actors June 2020 o Lack of open mirrored "registry" of reference, accessible to all, where to register a new threat actor name, or to access all already named threat actors. The "registry" can contain the time- based information mentionned above, it is a tool. This document proposes a set of guidelines to name threat actors. The goal is to reduce the above mentioned issues. 1.1. 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]. 2. Recommendations The recommendations listed below provide a minimal set of guidelines while assigning a new name to a threat actor. 2.1. Reusing threat actor naming Before creating a new threat actor name, you MUST consider a review of existing threat actor names from databases such as the threat actor MISP galaxy [MISP-G]. Proliferation of threat actor names is a significant challenge for the day-to-day analyst work. If your threat actor defined an existing threat actor, you MUST reuse an existing threat actor name. If there is no specific threat actor name, you SHALL create a new threat actor following the best practices defined in this document. 2.2. Uniqueness When choosing a threat actor name, uniqueness is a critical property. The threat actor name MUST be unique and not existing in different contexts. The name MUST not be a word from a dictionary which can be used in other contexts. 2.3. Format The name of the threat actor SHALL be composed of a single word. If there is multiple part like a decimal value such as a counter, the values MUST be separated with a dash. Single words are preferred to ease the search of keywords by analysts in public sources. Dulaunoy & Bourmeau Expires December 11, 2020 [Page 3] Internet-Draft Recommendations on naming threat actors June 2020 2.4. Encoding The name of the threat actor MUST be expressed in ASCII 7-bit. Assigning a localized name to a threat actor MAY create a set of ambiguity about different localized version of the same threat actor. 2.5. Don't confuse actor naming with malware naming The name of the threat actor MUST NOT be assigned based on the tools, techniques or patterns used by the threat actor. A notorious example in the threat intelligence community is Turla which can name a threat actor but also a malware used by this group or other groups. 2.6. Directory 3. Examples Some known examples are included below and serve as reference for good practices in naming threat actors. The below threat actor names can be considered good example: o APT-1 o TA-505 The below threat actor names can be considered as example to not follow: o GIF89a (Word also used for the GIF header) o ShadyRAT (Confusion between the name and the tool) o Group 3 (Common name used for other use-cases) o ZooPark (Name is used to describe something else) 4. Security Considerations Naming a threat actor could include specific sensitive reference to a case or an incident. Before releasing the naming, the creator MUST review the name to ensure no sensitive information is included in the threat actor name. 5. Acknowledgements The authors wish to thank all contributors who provided feedback via Twitter. Dulaunoy & Bourmeau Expires December 11, 2020 [Page 4] Internet-Draft Recommendations on naming threat actors June 2020 6. References 7. References 7.1. Normative References [MISP-G] Community, M., "MISP Galaxy - Public repository", . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . 7.2. Informative References [MISP-P] Community, M., "MISP Project - Open Source Threat Intelligence Platform and Open Standards For Threat Information Sharing", . Authors' Addresses Alexandre Dulaunoy Computer Incident Response Center Luxembourg 16, bd d'Avranches Luxembourg L-1160 Luxembourg Phone: +352 247 88444 Email: alexandre.dulaunoy@circl.lu Pauline Bourmeau Corexalys 26 Rue de la Bienfaisance Paris 75008 France Email: info@corexalys.com Dulaunoy & Bourmeau Expires December 11, 2020 [Page 5]