S0611: Clop

Clop is a ransomware family that was first observed in February 2019 and has been used against retail, transportation and logistics, education, manufacturing, engineering, automotive, energy, financial, aerospace, telecommunications, professional and legal services, healthcare, and high tech industries. Clop is a variant of the CryptoMix ransomware.[1][2][3]

EnterpriseS0611MalwareObject v1.0 Modified Apr 25, 2025, 14:44 UTC (UTC+00:00)

Clop is a Windows ransomware family documented by ATT&CK and associated with activity across many industries. Its defensive significance is not just encryption: the mapped behaviors include discovery of processes, files, shares, security software, registry modification, abuse of command shell and msiexec, service stopping, recovery inhibition, tool impairment, and data encryption for impact. For leaders, this makes Clop a useful ransomware readiness benchmark: can the organization detect preparation, containment blockers, and recovery sabotage before encryption becomes a business-continuity event?

Executive priority

Prioritize Clop as a resilience and evidence-readiness use case for Windows environments. The key business questions are whether critical file shares are monitored, whether recovery mechanisms are protected from tampering, whether SOC teams can see service stops and security-tool degradation, and whether incident responders can quickly identify affected hosts and preserve audit-quality evidence. ATT&CK also relates Clop to TA505, a cyber criminal group known for ransomware campaigns involving Clop, so threat intelligence teams should treat it as relevant context without assuming attribution in any local incident.

Technical view

Validate coverage against the ATT&CK relationships rather than relying on a single ransomware signature. For Windows endpoints, test visibility for cmd.exe execution, msiexec.exe abuse, registry changes, process and file discovery, network share discovery, security software discovery, service stop activity, recovery-inhibition behavior, security tool modification, packed or obfuscated binaries, code-signing metadata, time-based anti-analysis checks, and high-volume file encryption patterns. Because ATT&CK provides no official detection text for this object, SOC teams should map local analytics to the related techniques and verify that logs survive tool tampering and service disruption.

Likely telemetry

Windows endpoint process creation and command-line logs
Msiexec execution and parent-child process relationships
Registry modification events
File and directory enumeration activity
Network share and SMB access/enumeration telemetry

Detection direction

Do not depend only on ransomware hash or signature matching; the object maps to packing, obfuscation, and code-signing-related defense evasion.
Correlate discovery activity with later impact behaviors: process discovery, security software discovery, file/share enumeration, service stops, and recovery inhibition are more meaningful together than alone.
Tune false positives for legitimate administration tools such as cmd.exe, reg, service control, and msiexec by baselining expected administrators, software deployment systems, paths, and timing.
Confirm alerts still fire when security tools or logging agents are stopped, modified, or degraded.
Use the TA505 relationship as threat-intelligence context, not as automatic attribution for any observed activity.

Mitigation priorities

Harden and monitor Windows endpoints and servers that host business-critical files and shares.
Protect backups and recovery features from endpoint-level tampering, and test restore procedures independently of production hosts.
Restrict and monitor administrative utilities and living-off-the-land execution paths such as command shell, registry tools, service control, and msiexec where operationally feasible.
Ensure endpoint security tooling, logging agents, and alert pipelines have tamper monitoring and operational health checks.
Segment access to shared storage and critical services so discovery and encryption on one host does not automatically create enterprise-wide impact.

Analyst notes and limits

ATT&CK lists Clop as a Windows ransomware family and a CryptoMix variant first observed in February 2019, with cited reporting across retail, transportation and logistics, education, manufacturing, engineering, automotive, energy, financial, aerospace, telecommunications, professional and legal services, healthcare, and high tech industries. The most useful defensive value comes from the mapped techniques and the TA505 relationship, which together support ransomware preparedness, SOC validation, and incident-response planning.

No official ATT&CK detection guidance is provided for this object, and tactics are not specified on the malware object itself. Platform scope should be treated as Windows for Clop based on the supplied object, even though some related technique descriptions list additional platforms. Local telemetry, asset criticality, backup architecture, and control configuration are required to determine actual exposure or detection coverage.

Official MITRE ATT&CK definition

Clop

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.

Filter related techniques 17 rows

Domain	ID	Name	Relationship / procedure
Enterprise	T1518.001	Security Software Discovery Sub-technique	Clop can search for processes with antivirus and antimalware product names.[1][2]
Enterprise	T1489	Service Stop	Clop can kill several processes and services related to backups and security solutions.[3][1]
Enterprise	T1140	Deobfuscate/Decode Files or Information	Clop has used a simple XOR operation to decrypt strings.[1]
Enterprise	T1106	Native API	Clop has used built-in API functions such as WNetOpenEnumW(), WNetEnumResourceW(), WNetCloseEnum(), GetProcAddress(), and VirtualAlloc().[1][2]
Enterprise	T1497.003	Time Based Checks Sub-technique	Clop has used the `sleep` command to avoid sandbox detection.[3]
Enterprise	T1027.002	Software Packing Sub-technique	Clop has been packed to help avoid detection.[1][2]
Enterprise	T1614.001	System Language Discovery Sub-technique	Clop has checked the keyboard language using the GetKeyboardLayout() function to avoid installation on Russian-language or other Commonwealth of Independent States-language machines; it will also check the `GetTextCharset` function.[1]
Enterprise	T1083	File and Directory Discovery	Clop has searched folders and subfolders for files to encrypt.[1]
Enterprise	T1057	Process Discovery	Clop can enumerate all processes on the victim's machine.[1]
Enterprise	T1059.003	Windows Command Shell Sub-technique	Clop can use cmd.exe to help execute commands on the system.[2]
Enterprise	T1553.002	Code Signing Sub-technique	Clop can use code signing to evade detection.[3]
Enterprise	T1112	Modify Registry	Clop can make modifications to Registry keys.[2]
Enterprise	T1135	Network Share Discovery	Clop can enumerate network shares.[1]
Enterprise	T1490	Inhibit System Recovery	Clop can delete the shadow volumes with `vssadmin Delete Shadows /all /quiet` and can use bcdedit to disable recovery options.[1]
Enterprise	T1486	Data Encrypted for Impact	Clop can encrypt files using AES, RSA, and RC4 and will add the ".clop" extension to encrypted files.[1][3][2]
Enterprise	T1685	Disable or Modify Tools	Clop can uninstall or disable security products.[2]
Enterprise	T1218.007	Msiexec Sub-technique	Clop can use msiexec.exe to disable security tools on the system.[2]

Associated objects

Groups, software, and campaigns

G0092: TA505

TA505 is a cyber criminal group that has been active since at least 2014. TA505 is known for frequently changing malware, driving global trends in criminal malware distribution, and ransomware campaigns involving Clop.[1][2][3][4][5]

Relationship explorer

All related ATT&CK context

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: May 10, 2021, 23:19 UTC (UTC+00:00)
Modified: Apr 25, 2025, 14:44 UTC (UTC+00:00)
Raw hash: 5d5bb2e6bbae3767...

Imported snapshots across ATT&CK releases (1)

Release	Bundle imported	Object version	Modified	Status	Raw hash
19.1	Jun 3, 2026, 07:54 UTC (UTC+00:00)	1.0	Apr 25, 2025, 14:44 UTC (UTC+00:00)	Current bundle	`5d5bb2e6bbae…`

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]
Mcafee Clop Aug 2019

Mundo, A. (2019, August 1). Clop Ransomware. Retrieved May 10, 2021.
Open source URL
[2]
Cybereason Clop Dec 2020

Cybereason Nocturnus. (2020, December 23). Cybereason vs. Clop Ransomware. Retrieved May 11, 2021.
Open source URL
[3]
Unit42 Clop April 2021

Santos, D. (2021, April 13). Threat Assessment: Clop Ransomware. Retrieved July 30, 2021.
Open source URL
[4]
Clop

(Citation: Mcafee Clop Aug 2019)(Citation: Cybereason Clop Dec 2020)
[5]
mitre-attack S0611
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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