hashlookup format
draft-dulaunoy-hashlookup-format-00

Network Working Group                                        A. Dulaunoy
Internet-Draft                                               J-L. Huynen
Intended status: Informational                                     CIRCL
Expires: 6 March 2022                                   2 September 2021

                           hashlookup format
                  draft-dulaunoy-hashlookup-format-00

Abstract

   This document describes the hashlookup output format used to express
   meta information of hash values seen in databases of known files.
   The output description includes a common semantic.  The hashlookup
   format is used by public and private digital forensics investigations
   services.

Status of This Memo

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

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   This Internet-Draft will expire on 6 March 2022.

Copyright Notice

   Copyright (c) 2021 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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   Please review these documents carefully, as they describe your rights
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions and Terminology . . . . . . . . . . . . . . .   2
   2.  Format  . . . . . . . . . . . . . . . . . . . . . . . . . . .   2
     2.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   2
     2.2.  Fields format . . . . . . . . . . . . . . . . . . . . . .   3
       2.2.1.  Cryptographic hashing . . . . . . . . . . . . . . . .   3
       2.2.2.  Fuzzy hashing (Context Triggered Piecewise
               Hashing)  . . . . . . . . . . . . . . . . . . . . . .   3
       2.2.3.  Additional fields . . . . . . . . . . . . . . . . . .   3
       2.2.4.  Relationships fields  . . . . . . . . . . . . . . . .   4
     2.3.  Sample hashlookup output  . . . . . . . . . . . . . . . .   4
       2.3.1.  Binary file . . . . . . . . . . . . . . . . . . . . .   4
       2.3.2.  Binary file - package . . . . . . . . . . . . . . . .   5
   3.  Implementation  . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   6
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   6
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .   6
   8.  Informative References  . . . . . . . . . . . . . . . . . . .   6
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   6

1.  Introduction

   Digital forensics is a critical field in information security and
   especially incident response.  Providing intelligence about known set
   of files is crucial to avoid wasting efforts while conducting digital
   investigations. hashlookup format provides a common output format for
   diverse known databases of file hashes.  Those databases are, for
   example, the NIST National Software Reference Library (NSRL) or Known
   File Filter (KFF) lists used in digital forensics software.

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.  Format

2.1.  Overview

   The hashlookup format follows the JSON [RFC8259] format.  The intent
   of this output to be easily parsed by machines or generated by
   software in stream mode.  Each JSON object is expressed on a single
   line to be processed by the client line-by-line.  Examples of JSON
   output are presented below.

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2.2.  Fields format

   The main goal of the hashlookup format is to share common fields and
   to easily combine results from different sources.  As there is a wide
   variety of sources with various granularities of information
   available, the hashlookup format has been made quite lax regarding
   the mandatory fields.  The only condition is to have at least one
   cryptographic hash or fuzzy hashing value MUST be present in an
   hashlookup JSON object.

2.2.1.  Cryptographic hashing

   The cryptographic hashing value MUST be a JSON string.  The string
   represents the hashed value of the file represented.  The string MUST
   be the hexadecimal representation of the hash in upper case.

   *  "MD5"

   *  "SHA-1"

   *  "SHA-256"

2.2.2.  Fuzzy hashing (Context Triggered Piecewise Hashing)

   The fuzzy hashing value MUST be a JSON string.  The string represents
   the hashed value of the file represented.

   *  "TLSH"

   *  "SSDEEP"

2.2.3.  Additional fields

   Additional fields MAY be present to describe additional metadata from
   the file.  The value MUST be a JSON string.

   *  "FileName": Filename of the hashed file (NSRL)

   *  "FileSize": FileSize of the hashed file (NSRL)

   *  "CRC": CRC of the hashed file (NSRL)

   *  "SpecialCode": Special code of the hashed file (NSRL)

   *  "OpSystemCode": OpSystemCode of the hashed file (NSRL)

   *  "ProductCode": ProductCode of the hashed file (NSRL)

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   *  "PackageName": Package Name of the hashed file as seen in metadata
      of Debian pakage format, RPM or similar package managers (CIRCL)

   *  "PackageMaintainer": Package maintainer of the hashed file as seen
      in metadata of the Debian package format, RPM or similar package
      managers (CIRCL)

   *  "PackageSection": Package section of the hashed file as seen in
      the metadata of the Debian package format, RPM or similar package
      managers (CIRCL)

   *  "PackageVersion": Package version of the hashed file as seen in
      the metadata of the Debian package format, RPM or similar package
      managers (CIRCL)

   *  "KnownMalicious": List of source considering the hashed file as
      being malicious (CIRCL)

2.2.4.  Relationships fields

   Two OPTIONAL fields "parents" and "children" MAY be present to
   represent the relationships with other hashlookup objects.  The
   "parent" or "children" field MUST be a JSON array.  The value is a
   JSON string representing one the hashing algorithms.  The "SHA-1" is
   the RECOMMENDED algorithm for the relationship.  Other algorithms MAY
   be used if SHA-1 is not available.

2.3.  Sample hashlookup output

2.3.1.  Binary file

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{
  "CRC32": "B4DD44A4",
  "FileName": "./bin/ls",
  "FileSize": "110080",
  "MD5": "945FEDB3A3C290D69F075F997E5320FF",
  "OpSystemCode": {
    "MfgCode": "1006",
    "OpSystemCode": "362",
    "OpSystemName": "TBD",
    "OpSystemVersion": "none"
  },
  "ProductCode": {
    "ApplicationType": "Operating System",
    "Language": "English",
    "MfgCode": "534",
    "OpSystemCode": "599",
    "ProductCode": "163568",
    "ProductName": "Vinux ",
    "ProductVersion": "5.1"
  },
  "SHA-1": "5848386F77B4C60319C68B69C4594E29959381A2",
  "SHA-256": "08AC13B08BFE4407E0F0C2E12E7F5B1B5E77EB817349A5EA1D836E83CD5ACB13",
  "SpecialCode": "",
  "parents": [
    {
      "FileSize": "1090622",
      "MD5": "10A2318BE86F38A6ED113E16AABAA76B",
      "PackageDescription": "GNU core utilities\n This package contains the basic file, shell and text manipulation\n utilities which are expected to exist on every operating system.\n .\n Specifically, this package includes:\n arch base64 basename cat chcon chgrp chmod chown chroot cksum comm cp\n csplit cut date dd df dir dircolors dirname du echo env expand expr\n factor false flock fmt fold groups head hostid id install join link ln\n logname ls md5sum mkdir mkfifo mknod mktemp mv nice nl nohup nproc od\n paste pathchk pinky pr printenv printf ptx pwd readlink rm rmdir runcon\n sha*sum seq shred sleep sort split stat stty sum sync tac tail tee test\n timeout touch tr true truncate tsort tty uname unexpand uniq unlink\n users vdir wc who whoami yes",
      "PackageMaintainer": "Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>",
      "PackageName": "coreutils",
      "PackageSection": "utils",
      "PackageVersion": "8.21-1ubuntu5.4",
      "SHA-1": "F335B669CCB7BA8A2FC8FAF315B1B4BFF9D4217F",
      "SHA-256": "07995A739DAEBD60297F0E9C2B44DFAB0C735A0FE08FACC097ECE06BB4B9FA0B"
    }
  ]
}

2.3.2.  Binary file - package

{"FileSize": "1090622", "MD5": "10A2318BE86F38A6ED113E16AABAA76B", "PackageDescription": "GNU core utilities\n This package contains the basic file, shell and text manipulation\n utilities which are expected to exist on every operating system.\n .\n Specifically, this package includes:\n arch base64 basename cat chcon chgrp chmod chown chroot cksum comm cp\n csplit cut date dd df dir dircolors dirname du echo env expand expr\n factor false flock fmt fold groups head hostid id install join link ln\n logname ls md5sum mkdir mkfifo mknod mktemp mv nice nl nohup nproc od\n paste pathchk pinky pr printenv printf ptx pwd readlink rm rmdir runcon\n sha*sum seq shred sleep sort split stat stty sum sync tac tail tee test\n timeout touch tr true truncate tsort tty uname unexpand uniq unlink\n users vdir wc who whoami yes", "PackageMaintainer": "Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>", "PackageName": "coreutils", "PackageSection": "utils", "PackageVersion": "8.21-1ubuntu5.4", "SHA-1": "F335B669CCB7BA8A2FC8FAF315B1B4BFF9D4217F", "SHA-256": "07995A739DAEBD60297F0E9C2B44DFAB0C735A0FE08FACC097ECE06BB4B9FA0B", "children": ["9799864E326E9DB68121471C6E72EA45152BD2C8", "A880A1F35311A7D34C9B2CA10418BD6EE94EFF58", "3E9FE88BBFE594A701522C2BAF65E209FDF7EFD9", "E03605C7911BF75BE61E54FB922B11DCF1EAAFF9", "181A05F9D249BC99FB684984C631F149CC96990C", "7EF60EF3D83B352ACC9AF996ACDC7BE3DE955705", "C687BCF2FCB74F649163AAB837C15D5800D80B31", "168CA019316332AC0A01472BDF8769801F613DCA", "6645E63EC4411B54287CB0C1321160E44B05FB87", "1989E263AF6ACF6E2869D0B4CF9433E240213C4E", "DEDFD0DA98EA7D07A5B1C7D16EACDCD0154C79B9", "C1A0868024358B0C2F0A2991BD4676B70EBF66F3", "69952AAC37372161F66DA9B07FE0BE5263A9249F", "C03D2998DE9E4332DC91586F00DAC3CA5F4761C3", "E558E7B478FAC50CCACE0E6BE28CAA19FBC74D4E", "08E3AFA387417CB0DA343837D68374A4AB8D915F", "46750D0726DB8D8E4DF870B1060E2414B64164E9", "47A2C7B8518F7E790B097785E25C8E5909AE8A39", "9D8E3FD5BE0D04815F5B0606E94C3B7C29CC8788", "FCAD50919AF0544353E950D1B52E6E2C7B98854B", "CFDE9C955B1E774EF72FB2B4A3E180EADF4CD3D0", "95C37C6826FF0C4E1C17D08285D346EE643343C0", "B35FB1B6DCEC924603F8A86677DBB0D54F5B3C18", "F8592BBAF848DEF6DC26266B15246C50D45C2095", "FF43C49690FF5E5D05CA59D7E66CEEA7E3CE00D0", "903FA7065E10EA3ED8D07598715E7AA73C38BA5A", "64D49DB459A03800399A5BB8CFFE979A604959CF", "688FCF82E39A1C44424FE9F440B69B341FC8B6E2", "0A073CD0BBFB5A33F539003F85E4D90C4CA3F2BD", "C158DC6563C36EA34408E1A36D9786A8CD95FD22", "6ECEBFE6C408316371834A52A037D91EB5BD2A1E", "2411EE623576B90A80AF6B50C47E6186F8AB6308", "2592E88C4FD1BD34207E480AEF99508090370945", "3904F363902225998E2222D67D20D01579461C15", "76FCB8813682CC8697AF1E5C6DDD5FB1DFDEA23C", "D461D21F9994EA40C68651BCA6A6D07F43A551C4", "AEE56A85B66D037EAD8C2D630194C8C46E5C061A", "69AD64E3E922A40EC3372C5DBEE57E8ABE486227", "1348C730C44DF01C0D49DB6084B5736A1D7A3BBC", "E0A97820A852729E236F7524CC23060C7BD7638E", "BF2AAAEDAB78605C43FF12450381C07C15A01D06", "071E525B285AD74B3884F1661D857E8491D2C622", "087204A60FDF211A545A5B8B900F23C0AA118333", "5848386F77B4C60319C68B69C4594E29959381A2", "E19EC3D5E7B9AEC5320CE69FAE5A61EAA7AB2143", "A57FB1F8263E8AA32B36B0D08CDA214E55DE9202", "E8FC405D941E589AA1BAB01E05AD321A049B7775", "A9DB474B1F26FAF5E01B7D545D9CA66269487053", "5E49F9779E165B4EEE965914FECBB8F7D78C59C8", "B90EAF06CF7C6F829B5D671936B59052797F78AC", "90772F507D44570ECDF615B4C232F19FC6DD9D0D", "8025FBA333B4ADCE8EFCAD284541F38C41DA09DE", "F899AA531C826504B9B494C8EA5E4532313210A0", "6AE02146CEC01123843393817D352A805227807D", "3F9E530FB7E8C37E53FFCB1ECF977E00C25F224E", "416FD291494F58795077E5EE064D92329E15DE0E", "9A9A76DA8EC26B5AA3B1F35C434466291424718F", "731D8E470227AC5AAD8432EC123984B9D052B7A0", "EBE777F05B387155604065AD4BED08D2EA3CB8B8", "787ACF5E6A560B4AEB008111F701A730AADF2EC7", "AA6F74DAD038A0DFCD4D64A002482F40BB732F10", "16C68C5BD71D93E06C2D8FC7F0F0F73954C6D7C3", "4AA2F5D8C293531D72137EAE6F71044CD46B5AD7", "99F256008B4847D716492E9763D03D049EEECE6C", "3244B00D11BA9997243A3C2D3108FC915A4BA042", "9C7C38A4B21AACB6DC51AB8A97F6CDE6704ACCB6", "781A6E4FE0CB8167CE423FC476240BDED698D676", "A71230EDAE1E5D354C672E7AB1CE92BC6059EC7C", "ACBD8B51B76889C2F55820E1C32BB26FBF67C441", "7C394AF4519CE500161DEB17857B9C057B7C74B3", "7AB1711D45DB3752B7CBE446D2E0E62D77E75EE3", "8CD8BD2875A68CD5E01F4A071B3F39F5B725B2B6", "D5FF3DB00A37075C07878A718852AFE539C7610D", "1B56B7A2684EB25235DE1708ED1371CD7879540F", "53D8A8EF35DA82BB6118BF9D8BF1ED404FC383C9", "47392375E355F56961CA42E1CFB6B98BBD484D4C", "DCBD08101D550F76DCC1B7507B152734B6F7CE7C", "F8DF08929A667BED6D7086812C319DB522E8292C", "1FB274F0883E0075D398806ACD0FA765F1118C20", "583A638A220E6FD91569F4E263771D4F89F2CC67", "39698F9FA30AE6990ACDF69280B682D90705EC32", "DE762C72E9720DB70C1897C3E0FC9C8C7D160210", "283DD2D206477E4081911F6B83950EE76503EBAD", "A7C8E7F93AE9E86A7836238644274CD73C75F5A7", "A03537A232503853D9D4C30C732CFB5F12913D93", "3F4D980B4870D5A6EB3DF334CA49C5566000C97F", "C028089A484BA0AD0166281B58DEBE0C99E5B4E7", "4A46ECF0336D55076B1C72D2459139F85DF7236C", "DF9C0BDE30B1E2C8FAF8E35CBBD3672C0AE0DFDA", "29E52E423E17C0CE93D38AA8380B0A3AF137BC7E", "BA5FD03FF246DE181DDCAA744DC2AEF4D3711762", "FE7D945A453A276E1CD005AB7A1E177D48C63A86", "DD5A833CD33617F4DCDA0220809D41FA9B1EBFC7", "4017F5B69FBB5064E51A95C856437859BA6CBA83", "427B32F83A3FC5CA0813CBACE975ECA2D6AD918B", "8F16C526AF56EF4369611718463AD4975811DD20", "FC1C867CC2D89C5985C8CB833A3980915AF7E1A1", "EB3FCFD28830CCED7C6BAA04908F574EA4F2A61F", "410D1E55EE08EF6BD7DE39DE80A02981BAF151D1", "988B560C670EDD9E2AEEE6C1D6DE584518CC57F5", "F26ABF496FC9940BB06CD4CEC3D892CF2E426B6A", "22AC7B8CA7324408A18BB95FB55AAE9E5EA85785", "F3E09D476BB01366D740EFF92453AC73C8356F43", "6DD5ACA0C43EF39FD7FFAFEEDE46986985BC84DE", "E38EDB72D805F466556C8BB796EA729CBCC04245", "D6C447B56B702869E9B429A7B47E1CE3B57BED9A", "64E23452FA980EB5DD1D4375071CB6124CF9B196", "7883EB75715603F1B89449BE617F91C65698DF38", "C328540F2D947D50EF02AC958C0DCDB51CCA0DD0", "2AC91E34FE455B026B537EA8FBA86E69E251CEE4", "672D844C60553F9B3DB9844DC29DDF49BC426F45", "EDB7ED42160C95BA2C9DD4C1E87577BD85DFE5FB", "6F4DF90B509C9392A180D7C76BB0058D4C44A4BD", "1C75F8FAF710C17B87DFD75D8390F2F2F7AF6400", "C02435F5BE0DB85C12B47E33644322631CBE7CCA", "B0C07FAC1BA571EC3054D79C40181D99CB4D01ED", "CA0B3EBCD75D8799863ADDB66E9BD378A3B88F8E", "521E4CC97D2372F821F75DB03A26938F923C002C", "CFE1C6F349F1F0611CFD3B6DD0E60EB135D7D798", "DFC1F4C951F6E09B6CFCA69127BE483279A9B5F9", "6E957B4561B081DA16886751D729170975D860BE", "A570E581D7E1D5308E88154967C3BDE3593DA50D", "99CCB36AE5BA1B6EF528C3477CDB1185744C8DA7", "A07770FC93BAA888407523BB58EE9CE97C94DB02", "56035A58036F19A2C9D312BF2730C7F970B380CA", "2C3D857765A05AF072146796B07D6A063C0B7224", "4BD3020D460E50386297CE14F9AD85B7278F9A73", "7F8BF064B328BE934582341857413CE7A387CB81", "403645FFD3A5B16F3E558947C1854FAC180C1E92", "CC125B501A779D230063BA38A7BDEB93041D82D3", "9FC7AE958DAB28FE8B6466555BDFF954BE0EC2E7", "BAE0BFB8B27FC8806194C299435AD578BC93731A", "D357E7C22254E182377A57350BB9EC870B677B32", "9C3290446A139A29D000D920E83AE5ABA264C89A", "D3582A8EF775B8E3FB4771B7B6762FBF388C131E", "DBC34938767985B8C06471483D794A1ED91529A8", "23BEFDFDBD4FDE0052EE71D6E5561F2756C85F91", "53360CB53781CACC39BED7A4484A9B8AF7D356F4", "3E98B06F33CBB14590231B74BBC277418605BE21", "C41D8DEADD83B2FFDE06CD517452A680A87A44F3", "5942742E2461BF2646FDFA48C44F1BFDE7EC37EB", "D74E21CA765F9B05DE6535799A68DCA14DE3036B", "70090B7400AC6E18BE5E1C05FB6C0EC19EBB2B5A", "AF5BE22C07A95E8D7464415A5B988D7B46F34018", "24E177F4DDB835CBA8A12F9E1372E2338A2891E9", "D805D555362790B465829C15296CC9382898FAAC", "543D2D3AA93FAC487EAD738460539FB6EC9D8D52", "B20FEC67D2246000FD86FA211DD40CAAECCEB9AD", "7A806948FE658A5BAC29A0F5CA3710533D848565", "DC949A8C7FA9FEE929930B6FB599BC82F8DC4C5A", "55DBEAFBD6A4CA81E110CF0213051C11006AC4C9", "844D6D1DB5060B26976F07C66F2F8AAD2E455F65", "E7DAF9F24A6B790F157203235278CE3F4208CB45", "B32B2AC7FFE8F658378ECA63DCA037C64A867C95", "4326E056CE3813801B5DA2848248840D2E317C94", "CEC087401C965D8AF9D4DCFBDED5AD305C86697D", "EDF9B4EABA52E2A5570D936AD74C142E3CCE1CE8", "C04C8D4891153FAF0CF8E27CBC31A556862AB783", "47073CD75ED4721EEB6FF29C52D5D871771C57A4", "BEC391C559DAE7FFC0B5D90EA7CA65028AA1D16E", "5A11AC51F28545D7965990027CA63F28C410A51A", "66F6BE00855E7A2CB618F52C99F795A055534911", "75C44CAD971780BDCE8CE499F7ED7CA235985EC5", "87AA6E1E92AA2552DC6E431E88C22774E565F14E", "21C0A42179BF4A6C2E58DDF1A1BF58C668830A50", "8AF3BAAD4074A5267E6E7D8D77D0F0B0AADFEFC4", "5B74838880C11A9FEF94FDA3964DD6BA53F812E7", "F5C5CF75A119FF8818283B9CC932217888CDC8A9", "1056EBBFBBBF2E51BCB8A48FF8038CF66095F63A", "55016AD7A449B91A5DBE59308BDD3E84261A8FF9", "F0BC5D070A82BBCD1749EBE219671FEEEAEDAED6", "3884371FFF88B50CB05D50549A1A3C106017862C", "5EEC0C5A87A28238955970C668BA4DD733A27380", 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"861C814423F49B97077D4910FAB0C02D54EAB4B1", "44B78AF79C57BD5235883D15EC3106F96A2A5AA9", "BCF5A7EB0FD6362BB317BA69D7925002C7E1E3BE", "E0878F0243391A4537E0DF1652BE8D506FA749D1", "134A47F790EE082AB9A7E2503F01B0C164D777E8", "9352FF68CF7B5E73E7434BF138AFC2E17FB4545B", "3E6791CD56A48FABC6F637BE11D234E8068EF91F", "6F6A5B2A733ADBBB1100C44233DFBD3C5D00E4EA", "BB7E54487E24D3778C2C0EAB965AA421EA9D4D0F", "B7A599586D2BD1B69C69EB0862BC665DAAD9FC61", "2B129FA27E458F767898FD152EB65047B65238FE", "4D34641032551FBEBFFDAF751B707B90F9570C4D", "912A4B72F98C0EBEF5C235A55F49BA5EC5E463D9", "32D82E8E9873FEA2613B882461C58E13AB6BE52B", "F0C41EB583D4B17416DD70F1079E6FDEACE144FD", "014D78C0ECB1ED495D12E4FA0DA9C7A6A953945F", "4E492E947E446DF5D4B19AAB08664D65A3E604AE"]}

3.  Implementation

   A public hashlookup service [HASHLOOKUP-SERVICE] is provided by CIRCL
   and accessible as a ReST HTTP API.  A software back-end
   implementation which produces a hashlookup format output is available
   [HASHLOOKUP-SERVER].

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4.  Security Considerations

   hashlookup results events might contain sensitive or confidential
   information.  Adequate access control and encrypted transport layer
   shall be implemented to ensure the confidentiality of the hashlookup
   results.

   hashlookup results don't imply a specific assumption concerning the
   maliciousness or non-maliciousness of a file. hashlookup only
   provides the information about the presence of a file in a specific
   set, known source or database.

5.  Acknowledgements

   The authors wish to thank all the users of the CIRCL hashlookup
   services for their feedback.

6.  References

7.  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>.

   [RFC8259]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
              Interchange Format", STD 90, RFC 8259,
              DOI 10.17487/RFC8259, December 2017,
              <https://www.rfc-editor.org/info/rfc8259>.

8.  Informative References

   [HASHLOOKUP-SERVER]
              Dulaunoy, A., "hashlookup-server is a minimal and fast
              open source server (ReST/API) to lookup quickly hash value
              from large dataset.",
              <https://github.com/adulau/hashlookup-server>.

   [HASHLOOKUP-SERVICE]
              CIRCL.LU, "CIRCL hash lookup is a public API to lookup
              hash values against known database of files.",
              <https://www.circl.lu/services/hashlookup/>.

Authors' Addresses

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   Alexandre Dulaunoy
   Computer Incident Response Center Luxembourg
   16, bd d'Avranches
   L-L-1160 Luxembourg
   Luxembourg

   Phone: +352 247 88444
   Email: alexandre.dulaunoy@circl.lu

   Jean-Louis Huynen
   Computer Incident Response Center Luxembourg
   16, bd d'Avranches
   L-L-1160 Luxembourg
   Luxembourg

   Phone: +352 247 88444
   Email: jean-louis.huynen@circl.lu

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