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MITRE ATT&CK® Campaign

C0021: C0021

C0021 was a spearphishing campaign conducted in November 2018 that targeted public sector institutions, non-governmental organizations (NGOs), educational institutions, and private-sector corporations in the oil and gas, chemical, and hospitality industries. The majority of targets were located in the US, particularly in and around Washington D.C., with other targets located in Europe, Hong Kong, India, and Canada. C0021's technical artifacts, tactics, techniques, and procedures (TTPs), and targeting overlap with previous suspected APT29 activity.[1][2]

EnterpriseC0021CampaignObject v1.0 Modified
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Glexia's Take

Analyst context for executives and security teams

Analyst confidence Medium

C0021 matters because it shows how a targeted spearphishing-link campaign can combine social engineering, staged infrastructure, obfuscated payloads, PowerShell, legitimate execution utilities, and Cobalt Strike-style post-exploitation tooling. For leaders, the practical issue is not the 2018 date alone; it is whether the organization can prove that email, identity, endpoint, and network teams would see and contain this chain before it becomes a broader intrusion.

Executive priority

Prioritize this as a resilience and evidence problem: can the business demonstrate controls against targeted phishing links, payload download, command execution, and command-and-control traffic? The campaign targeted public sector, NGOs, education, and several private-sector industries including oil and gas, chemical, and hospitality, so risk owners in similar environments should use it to test phishing readiness, incident response handoffs, and audit evidence for email security, endpoint logging, and network monitoring. Treat the reported overlap with suspected APT29 activity as context, not as a definitive attribution claim.

Technical view

SOC and IR teams should validate visibility across the relationship chain: spearphishing links and user click activity; execution via PowerShell and rundll32; embedded or obfuscated payloads and later deobfuscation/decoding; ingress tool transfer; C2 over web protocols, non-application-layer protocols, and encrypted/asymmetric channels; and use of Cobalt Strike. Because ATT&CK provides no official detection text for this campaign, detection engineering should map controls to the related techniques rather than relying on campaign-level indicators.

Likely telemetry

  • Email security logs for inbound messages, URLs, sender metadata, and user click events
  • Identity provider and Office Suite logs related to link access and authentication context
  • Endpoint process creation telemetry, especially PowerShell and rundll32 command lines
  • Script block, command-line, and file creation telemetry where available
  • Web proxy, DNS, firewall, and network flow logs for outbound web and non-application-layer communications

Detection direction

  • Test whether phishing-link detections preserve enough context to connect email delivery, URL click, payload retrieval, and endpoint execution.
  • Tune PowerShell and rundll32 analytics for suspicious parent-child process chains, unusual command-line structure, and encoded or obfuscated content while accounting for legitimate administrative use.
  • Validate detections for payload staging and tool transfer from external infrastructure, especially where web traffic may appear routine.
  • Look for Cobalt Strike-related behavior through behavioral analytics rather than assuming tool-name signatures are sufficient.
  • Correlate host and network telemetry because web protocols, encrypted communications, and non-application-layer protocols can reduce visibility if monitored in isolation.

Mitigation priorities

  • Strengthen phishing-link defenses first: email filtering, URL inspection, user reporting workflows, and rapid takedown/blocking processes.
  • Harden identity and Office Suite access paths with conditional access, strong authentication, and monitoring of suspicious link-driven sessions where applicable.
  • Constrain and monitor scripting and living-off-the-land execution, especially PowerShell and rundll32 on Windows endpoints.
  • Ensure endpoint controls can inspect downloaded files, embedded payloads, obfuscated content, and decoding activity.
  • Restrict unnecessary outbound traffic and maintain proxy, DNS, firewall, and network telemetry for investigation.
Analyst notes and limits

The official campaign description states that C0021 was a November 2018 spearphishing campaign targeting public sector institutions, NGOs, educational institutions, and private-sector corporations in oil and gas, chemical, and hospitality, with most targets in the US and others in Europe, Hong Kong, India, and Canada. It also states technical artifacts, TTPs, and targeting overlapped with previous suspected APT29 activity. This take uses that as contextual intelligence only and focuses on defensive validation against the related ATT&CK techniques and Cobalt Strike relationship.

ATT&CK supplies no official detection text, no campaign-level platforms or tactics, and no local indicators in the provided object. Any statement about current exposure, active exploitation, attribution, or coverage requires environment-specific telemetry and intelligence beyond the supplied fields.

Official MITRE ATT&CK definition

C0021

C0021 was a spearphishing campaign conducted in November 2018 that targeted public sector institutions, non-governmental organizations (NGOs), educational institutions, and private-sector corporations in the oil and gas, chemical, and hospitality industries. The majority of targets were located in the US, particularly in and around Washington D.C., with other targets located in Europe, Hong Kong, India, and Canada. C0021's technical artifacts, tactics, techniques, and procedures (TTPs), and targeting overlap with previous suspected APT29 activity.[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.

15 rows
Domain ID Name Relationship / procedure
Enterprise T1583.001 Domains Sub-technique

For C0021, the threat actors registered domains for use in C2.CitationFireEye APT29 Nov 2018
Enterprise T1218.011 Rundll32 Sub-technique

During C0021, the threat actors used `rundll32.exe` to execute the Cobalt Strike Beacon loader DLL.CitationFireEye APT29 Nov 2018
Enterprise T1027.010 Command Obfuscation Sub-technique

During C0021, the threat actors used encoded PowerShell commands.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1584.001 Domains Sub-technique

For C0021, the threat actors used legitimate but compromised domains to host malicious payloads.CitationMicrosoft Unidentified Dec 2018
Enterprise T1204.001 Malicious Link Sub-technique

During C0021, the threat actors lured users into clicking a malicious link which led to the download of a ZIP archive containing a malicious .LNK file.CitationFireEye APT29 Nov 2018
Enterprise T1095 Non-Application Layer Protocol

During C0021, the threat actors used TCP for some C2 communications.CitationFireEye APT29 Nov 2018
Enterprise T1588.002 Tool Sub-technique

For C0021, the threat actors used Cobalt Strike configured with a modified variation of the publicly available Pandora Malleable C2 Profile.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1071.001 Web Protocols Sub-technique

During C0021, the threat actors used HTTP for some of their C2 communications.CitationFireEye APT29 Nov 2018
Enterprise T1608.001 Upload Malware Sub-technique

For C0021, the threat actors uploaded malware to websites under their control.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1105 Ingress Tool Transfer

During C0021, the threat actors downloaded additional tools and files onto victim machines.CitationMicrosoft Unidentified Dec 2018CitationFireEye APT29 Nov 2018
Enterprise T1140 Deobfuscate/Decode Files or Information

During C0021, the threat actors deobfuscated encoded PowerShell commands including use of the specific string `'FromBase'+0x40+'String'`, in place of `FromBase64String` which is normally used to decode base64.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1566.002 Spearphishing Link Sub-technique

During C0021, the threat actors sent phishing emails with unique malicious links, likely for tracking victim clicks.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1573.002 Asymmetric Cryptography Sub-technique

During C0021, the threat actors used SSL via TCP port 443 for C2 communications.CitationFireEye APT29 Nov 2018
Enterprise T1059.001 PowerShell Sub-technique

During C0021, the threat actors used obfuscated PowerShell to extract an encoded payload from within an .LNK file.CitationFireEye APT29 Nov 2018CitationMicrosoft Unidentified Dec 2018
Enterprise T1027.009 Embedded Payloads Sub-technique

For C0021, the threat actors embedded a base64-encoded payload within a LNK file.CitationMicrosoft Unidentified Dec 2018
Associated objects

Groups, software, and campaigns

Malware Enterprise

S0154: Cobalt Strike

Cobalt Strike is a commercial, full-featured, remote access tool that bills itself as “adversary simulation software designed to execute targeted attacks and emulate the post-exploitation actions of advanced threat actors”. Cobalt Strike’s interactive post-exploit capabilities cover the full range of ATT&CK tactics, all executed within a single, integrated system.[1]

In addition to its own capabilities, Cobalt Strike leverages the capabilities of other well-known tools such as Metasploit and Mimikatz.[1]

LinuxmacOSWindows
Relationship explorer

All related ATT&CK context

uses · Technique T1583.001: Domains Enterprise uses · Technique T1218.011: Rundll32 Enterprise uses · Technique T1027.010: Command Obfuscation Enterprise uses · Technique T1584.001: Domains Enterprise uses · Technique T1204.001: Malicious Link Enterprise uses · Technique T1095: Non-Application Layer Protocol Enterprise uses · Technique T1588.002: Tool Enterprise uses · Technique T1071.001: Web Protocols Enterprise uses · Technique T1608.001: Upload Malware Enterprise uses · Technique T1105: Ingress Tool Transfer Enterprise uses · Technique T1140: Deobfuscate/Decode Files or Information Enterprise uses · Technique T1566.002: Spearphishing Link Enterprise uses · Malware S0154: Cobalt Strike Enterprise uses · Technique T1573.002: Asymmetric Cryptography Enterprise uses · Technique T1059.001: PowerShell Enterprise uses · Technique T1027.009: Embedded Payloads Enterprise
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
1.0
Created
Modified
Raw hash
11fb25f7b47fa27b...
Imported snapshots across ATT&CK releases (1)
Release Bundle imported Object version Modified Status Raw hash
19.1 1.0 Current bundle 11fb25f7b47f…
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 JSON Open 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]
    Microsoft Unidentified Dec 2018

    Microsoft Defender Research Team. (2018, December 3). Analysis of cyberattack on U.S. think tanks, non-profits, public sector by unidentified attackers. Retrieved April 15, 2019.

    Open source URL
  2. [2]
    FireEye APT29 Nov 2018

    Dunwoody, M., et al. (2018, November 19). Not So Cozy: An Uncomfortable Examination of a Suspected APT29 Phishing Campaign. Retrieved November 27, 2018.

    Open source URL
  3. [3]
    mitre-attack C0021
    Open source URL
Source and licensing

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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