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MITRE ATT&CK® Malware

S0353: NOKKI

NOKKI is a modular remote access tool. The earliest observed attack using NOKKI was in January 2018. NOKKI has significant code overlap with the KONNI malware family. There is some evidence potentially linking NOKKI to APT37.[1][2]

EnterpriseS0353MalwareObject v1.2Modified
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Glexia's Take · Automated analysis

Security context for executives and security teams

Automation confidenceMedium

NOKKI matters because ATT&CK describes it as a Windows modular remote access tool with behaviors that span discovery, credential collection, persistence, stealth, local staging, tool transfer, and command-and-control over web or file-transfer protocols. For leaders, the decision value is not the malware name alone; it is whether the organization can recognize a Windows host that is being inventoried, made persistent, used to stage data, and controlled through traffic that may resemble normal web or file-transfer activity.

Executive priority

Treat NOKKI as a readiness test for Windows endpoint visibility, identity exposure, and incident response triage. The ATT&CK relationships show behaviors that can affect business continuity and investigation quality: credential API hooking can increase identity risk, Run Key or Startup Folder persistence can extend dwell time, file deletion and obfuscation can reduce forensic evidence, and local data staging plus C2/file transfer behaviors can complicate containment decisions. Security leaders should ask whether SOC and IR teams can connect host discovery, suspicious rundll32 use, persistence changes, staged files, and unusual outbound protocols into one incident narrative instead of handling each alert in isolation.

Technical view

ATT&CK provides no official detection text for NOKKI, so defenders should validate coverage through the related techniques rather than relying on a malware-specific analytic. Focus on Windows telemetry for: system and user discovery, network and storage discovery, Run Key or Startup Folder changes, rundll32-mediated execution, credential API hooking indicators where available, obfuscated or decoded payload artifacts, file deletion after execution, local staging paths, ingress tool transfer, and outbound C2 using web or file-transfer protocols. Relationship context also notes Kimsuky uses this malware and the description says there is some evidence potentially linking NOKKI to APT37, but those links should be used for threat-intelligence enrichment, not as proof of attribution in a local incident.

Likely telemetry

  • Windows endpoint process creation and command-line telemetry, especially rundll32.exe and discovery utilities
  • Windows Registry and Startup Folder modification events for persistence validation
  • File creation, modification, deletion, and staging-location telemetry
  • Endpoint security alerts or memory/behavioral telemetry relevant to API hooking and credential-access behavior
  • Network connection, proxy, DNS, and web request logs for HTTP/S or other web-protocol C2 patterns

Detection direction

  • Build behavior-based correlation around the ATT&CK-linked techniques rather than depending on the NOKKI name or hash alone.
  • Tune for suspicious rundll32 execution, but account for legitimate administrative and software activity to reduce false positives.
  • Monitor Run Key and Startup Folder changes with parent process, user context, and file path reputation to distinguish normal installers from suspicious persistence.
  • Correlate discovery commands or API calls with subsequent staging, tool transfer, persistence, or outbound network activity; discovery alone can be noisy.
  • Review web and file-transfer egress controls and logs for uncommon destinations, unusual user-agent or timing patterns, and unexpected transfer activity from Windows endpoints.

Mitigation priorities

  • Prioritize Windows endpoint visibility for process, registry, file, and network events before relying on malware-family-specific detections.
  • Harden and monitor persistence locations such as Registry Run Keys and Startup Folders, with change-review processes for high-value systems.
  • Restrict and monitor unnecessary outbound file-transfer protocols and ensure web egress is logged through controlled paths where feasible.
  • Apply least privilege and credential protection practices to reduce the value of credential-access behavior such as API hooking.
  • Improve incident response playbooks for modular RAT activity: preserve volatile evidence, collect persistence artifacts, review staged data, and scope related C2 and tool-transfer activity.
Additional notes and limits

The object is a malware entry for NOKKI, described by ATT&CK as a modular remote access tool first observed in January 2018 with significant code overlap with KONNI. ATT&CK also states there is some evidence potentially linking NOKKI to APT37, and the supplied relationship context says Kimsuky uses this object. These relationships are useful for prioritizing intelligence review and hunt hypotheses, but they are not sufficient by themselves for attribution or impact assessment.

ATT&CK provides no official detection guidance for NOKKI, and the object’s own platform field is Windows while several related techniques list broader platforms. This take therefore emphasizes Windows validation and technique-based coverage. Local environment evidence is required to determine whether telemetry exists, whether controls are effective, and whether any observed activity is malicious.

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Official MITRE ATT&CK definition

NOKKI

NOKKI is a modular remote access tool. The earliest observed attack using NOKKI was in January 2018. NOKKI has significant code overlap with the KONNI malware family. There is some evidence potentially linking NOKKI to APT37.[1][2]

View the same entry on attack.mitre.org (MITRE-hosted reference; in-page links above use the Glexia ATT&CK library.)

Glexia analysis

How security teams should use this page

Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.

ATT&CK relationship table

Techniques used

This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.

16 rows
DomainIDNameRelationship / procedure
EnterpriseT1124System Time Discovery

NOKKI can collect the current timestamp of the victim's machine.[1]

EnterpriseT1547.001Registry Run Keys / Startup FolderSub-technique

NOKKI has established persistence by writing the payload to the Registry key HKCU\Software\Microsoft\Windows\CurrentVersion\Run.[1]

EnterpriseT1105Ingress Tool Transfer

NOKKI has downloaded a remote module for execution.[1]

EnterpriseT1036.005Match Legitimate Resource Name or LocationSub-technique

NOKKI is written to %LOCALAPPDATA%\MicroSoft Updatea\svServiceUpdate.exe prior being executed in a new process in an apparent attempt to masquerade as a legitimate folder and file.[1]

EnterpriseT1027Obfuscated Files or Information

NOKKI uses Base64 encoding for strings.[1]

EnterpriseT1070.004File DeletionSub-technique

NOKKI can delete files to cover tracks.[1]

EnterpriseT1033System Owner/User Discovery

NOKKI can collect the username from the victim’s machine.[1]

EnterpriseT1218.011Rundll32Sub-technique

NOKKI has used rundll32 for execution.[1]

EnterpriseT1140Deobfuscate/Decode Files or Information

NOKKI uses a unique, custom de-obfuscation technique.[1]

EnterpriseT1680Local Storage Discovery

NOKKI can gather information on drives on the victim’s machine.[1]

EnterpriseT1071.001Web ProtocolsSub-technique

NOKKI has used HTTP for C2 communications.[1]

EnterpriseT1074.001Local Data StagingSub-technique

NOKKI can collect data from the victim and stage it in LOCALAPPDATA%\MicroSoft Updatea\uplog.tmp.[1]

EnterpriseT1016System Network Configuration Discovery

NOKKI can gather information on the victim IP address.[1]

EnterpriseT1056.004Credential API HookingSub-technique

NOKKI uses the Windows call SetWindowsHookEx and begins injecting it into every GUI process running on the victim's machine.[1]

EnterpriseT1071.002File Transfer ProtocolsSub-technique

NOKKI has used FTP for C2 communications.[1]

EnterpriseT1082System Information Discovery

NOKKI can gather information on the operating system on the victim’s machine.[1]

Associated objects

Groups, software, and campaigns

GroupEnterprise

G0094: Kimsuky

Kimsuky is a Democratic People's Republic of Korea (DPRK)-based cyber espionage group that has been active since at least 2012. The group initially targeted South Korean government agencies, think tanks, and subject-matter experts in various fields. Its operations expanded to include the United Nations and organizations in the government, education, business services, and manufacturing sectors across the United States, Japan, Russia, and Europe. Kimsuky has focused collection on foreign policy and national security issues tied to the Korean Peninsula, nuclear policy, and sanctions. Kimsuky operations have overlapped with those of other North Korean state-sponsored cyber espionage actors as a result of ad hoc collaborations or other limited resource sharing.[1][2][3][4][5][6]

Kimsuky was assessed to be responsible for the 2014 Korea Hydro & Nuclear Power Co. compromise; other notable campaigns include Operation STOLEN PENCIL (2018), Operation Kabar Cobra (2019), and Operation Smoke Screen (2019).[7][8][9] In 2023, Kimsuky was observed using commercial large language models (LLMs) to assist with vulnerability research, scripting, social engineering and reconnaissance.[10]

DPRK threat actor cluster boundaries overlap in open source reporting, with some security researchers consolidating all attributed North Korean state-sponsored cyber activity under Lazarus Group, rather than tracking operationally distinct subgroups.

Relationship explorer

All related ATT&CK context

uses · TechniqueT1124: System Time DiscoveryEnterpriseuses · TechniqueT1547.001: Registry Run Keys / Startup FolderEnterpriseuses · TechniqueT1105: Ingress Tool TransferEnterpriseuses · TechniqueT1036.005: Match Legitimate Resource Name or LocationEnterpriseuses · TechniqueT1027: Obfuscated Files or InformationEnterpriseuses · GroupG0094: KimsukyEnterpriseuses · TechniqueT1070.004: File DeletionEnterpriseuses · TechniqueT1033: System Owner/User DiscoveryEnterpriseuses · TechniqueT1218.011: Rundll32Enterpriseuses · TechniqueT1140: Deobfuscate/Decode Files or InformationEnterpriseuses · TechniqueT1680: Local Storage DiscoveryEnterpriseuses · TechniqueT1071.001: Web ProtocolsEnterpriseuses · TechniqueT1074.001: Local Data StagingEnterpriseuses · TechniqueT1016: System Network Configuration DiscoveryEnterpriseuses · TechniqueT1056.004: Credential API HookingEnterpriseuses · TechniqueT1071.002: File Transfer ProtocolsEnterpriseuses · TechniqueT1082: System Information DiscoveryEnterprise
Change history

Object version and sync metadata

The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.

ATT&CK release
19.1
Object version
1.2
Created
Modified
Raw hash
60c5b9506005847c...
Imported snapshots across ATT&CK releases(1)
ReleaseBundle importedObject versionModifiedStatusRaw hash
19.11.2Current bundle60c5b9506005…
Raw source

Mirrored ATT&CK source object

The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.

Open mirrored raw JSONOpen MITRE-hosted copy
Source references

External references and citations

MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.

  1. [1]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  2. [2]
    Unit 42 Nokki Oct 2018

    Grunzweig, J. (2018, October 01). NOKKI Almost Ties the Knot with DOGCALL: Reaper Group Uses New Malware to Deploy RAT. Retrieved November 5, 2018.

    Open source URL
  3. [3]
    Crowdstrike GTR2020 Mar 2020

    Crowdstrike. (2020, March 2). 2020 Global Threat Report. Retrieved December 11, 2020.

    Open source URL
  4. [4]
    NOKKI

    (Citation: Unit 42 NOKKI Sept 2018)

  5. [5]
    NOKKI

    (Citation: Unit 42 NOKKI Sept 2018)

  6. [6]
    NOKKI

    (Citation: Unit 42 NOKKI Sept 2018)

  7. [7]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  8. [8]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  9. [9]
    Unit 42 Nokki Oct 2018

    Grunzweig, J. (2018, October 01). NOKKI Almost Ties the Knot with DOGCALL: Reaper Group Uses New Malware to Deploy RAT. Retrieved November 5, 2018.

    Open source URL
  10. [10]
    Unit 42 Nokki Oct 2018

    Grunzweig, J. (2018, October 01). NOKKI Almost Ties the Knot with DOGCALL: Reaper Group Uses New Malware to Deploy RAT. Retrieved November 5, 2018.

    Open source URL
  11. [11]
    mitre-attackS0353
    Open source URL
  12. [12]
    mitre-attackS0353
    Open source URL
  13. [13]
    mitre-attackS0353
    Open source URL
  14. [14]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  15. [15]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  16. [16]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  17. [17]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  18. [18]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  19. [19]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  20. [20]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  21. [21]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  22. [22]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  23. [23]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  24. [24]
    Crowdstrike GTR2020 Mar 2020

    Crowdstrike. (2020, March 2). 2020 Global Threat Report. Retrieved December 11, 2020.

    Open source URL
  25. [25]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  26. [26]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  27. [27]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  28. [28]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  29. [29]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  30. [30]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  31. [31]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  32. [32]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  33. [33]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  34. [34]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  35. [35]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  36. [36]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  37. [37]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  38. [38]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  39. [39]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  40. [40]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  41. [41]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
  42. [42]
    Unit 42 NOKKI Sept 2018

    Grunzweig, J., Lee, B. (2018, September 27). New KONNI Malware attacking Eurasia and Southeast Asia. Retrieved November 5, 2018.

    Open source URL
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Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.

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