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MITRE ATT&CK® Technique

T1204.005: Malicious Library

Adversaries may rely on a user installing a malicious library to facilitate execution. Threat actors may Upload Malware to package managers such as NPM and PyPi, as well as to public code repositories such as GitHub. User may install libraries without realizing they are malicious, thus bypassing techniques that specifically achieve Initial Access. This can lead to the execution of malicious code, such as code that establishes persistence, steals data, or mines cryptocurrency.[1][2]

In some cases, threat actors may compromise and backdoor existing popular libraries (i.e., Compromise Software Dependencies and Development Tools). Alternatively, they may create entirely new packages and leverage behaviors such as typosquatting to encourage users to install them.

EnterpriseT1204.005Sub-techniqueObject v1.0Modified
Glexia's Take · Automated analysis

Security context for executives and security teams

Automation confidenceHigh

Malicious Library matters because normal developer or user activity—installing a package from a package manager or public repository—can become the execution path for adversary code. The business risk is not only malware on an endpoint; it is trust in the software supply chain, developer workstations, build environments, and open-source dependency intake across Linux, macOS, and Windows.

Executive priority

Prioritize this where employees, contractors, or developers can install packages from sources such as NPM, PyPI, or public code repositories without approval or monitoring. Leaders should ask whether software installation rights, dependency governance, user training, and network prevention controls are sufficient to produce audit-ready evidence and support fast incident decisions when a suspicious package is found.

Technical view

This is an execution sub-technique under User Execution. SOC, IR, and detection engineering teams should validate visibility into user-initiated library/package installation activity on Linux, macOS, and Windows, especially from package managers and public repositories. ATT&CK provides no official detection text for this object, but the related detection strategy DET0252 specifically covers user-initiated malicious library installation via package manager. Detection work should focus on correlating package installation events with process execution, network connections, file writes, persistence attempts, data access, or cryptocurrency-mining-like behavior where locally observable.

Likely telemetry

  • Package manager install activity such as NPM or PyPI package installation logs where available
  • Endpoint process creation and command-line telemetry tied to package manager or interpreter activity
  • File creation and modification events in user, project, dependency, and library paths
  • Network connections initiated during or shortly after package installation
  • Endpoint security alerts for suspicious code execution, persistence, data theft, or mining behavior

Detection direction

  • Use DET0252 as the starting point for package-manager-focused detections rather than relying on generic malware alerts alone.
  • Baseline expected package installation behavior by role, especially for developers, build systems, and power users, to reduce false positives.
  • Correlate install events with immediate execution and follow-on behaviors; the technique is about user-facilitated execution, not merely the presence of an unfamiliar package.
  • Validate visibility across Linux, macOS, and Windows because the ATT&CK object lists all three platforms.
  • Account for blind spots where package manager logs are not centralized, developers use personal environments, or endpoint telemetry does not capture command-line arguments and child processes.

Mitigation priorities

  • Limit software installation privileges and enforce approved installation paths using the M1033 mitigation direction.
  • Pair technical restrictions with user training under M1017 so users understand package-name spoofing, typosquatting risk, and reporting expectations for suspicious libraries.
  • Use network intrusion prevention under M1031 where signatures or policy controls can block known malicious traffic at network boundaries.
  • For higher-risk developer and build environments, require review of new dependencies and maintain evidence of authorized package sources and installation activity.
  • Prepare IR playbooks for suspicious library discovery: identify affected hosts/projects, determine install source and time, review execution and network activity, and remove or block unauthorized packages.
Additional notes and limits

The supplied ATT&CK description highlights malicious packages uploaded to package managers such as NPM and PyPI, public repositories such as GitHub, compromised/backdoored popular libraries, and newly created packages using typosquatting. The object is a new enterprise ATT&CK sub-technique in version 19.1 and is scoped to execution on Linux, macOS, and Windows.

Official ATT&CK detection guidance is not provided for this object. Telemetry and control recommendations are therefore derived from the object description, listed platforms and tactic, and supplied relationships to DET0252, M1017, M1031, and M1033. Local package ecosystems, developer workflows, logging coverage, and software approval processes are required to assess real exposure or detection quality.

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

Official MITRE ATT&CK definition

Malicious Library

Adversaries may rely on a user installing a malicious library to facilitate execution. Threat actors may Upload Malware to package managers such as NPM and PyPi, as well as to public code repositories such as GitHub. User may install libraries without realizing they are malicious, thus bypassing techniques that specifically achieve Initial Access. This can lead to the execution of malicious code, such as code that establishes persistence, steals data, or mines cryptocurrency.[1][2]

In some cases, threat actors may compromise and backdoor existing popular libraries (i.e., Compromise Software Dependencies and Development Tools). Alternatively, they may create entirely new packages and leverage behaviors such as typosquatting to encourage users to install them.

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

Related techniques

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.

1 rows
DomainIDNameRelationship / procedure
EnterpriseT1204User ExecutionThis object subtechnique of User Execution.
Associated objects

Groups, software, and campaigns

Relationship explorer

All related ATT&CK context

Mitigations

Mitigation direction

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
982596ea33ee33be...
Imported snapshots across ATT&CK releases(1)
ReleaseBundle importedObject versionModifiedStatusRaw hash
19.11.0Current bundle982596ea33ee…
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.

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]
    Datadog Security Labs Malicious PyPi Packages 2024

    Sebastian Obregoso and Christophe Tafani-Dereeper. (2024, May 23). Malicious PyPI packages targeting highly specific MacOS machines. Retrieved May 22, 2025.

    Open source URL
  2. [2]
    Fortinet Malicious NPM Packages 2023

    Jin Lee and Jenna Wang. (2023, October 2). Malicious Packages Hidden in NPM. Retrieved May 22, 2025.

    Open source URL
  3. [3]
    Sentinel One Contagious Interview ClickFix September 2025

    Aleksandar Milenkoski, Sreekar Madabushi, Kenneth Kinion. (2025, September 4). Contagious Interview | North Korean Threat Actors Reveal Plans and Ops by Abusing Cyber Intel Platforms. Retrieved October 20, 2025.

    Open source URL
  4. [4]
    Validin Contagious Interview North Korea ClickFix January 2025

    Efstratios Lontzetidis. (2025, January 16). Lazarus APT: Techniques for Hunting Contagious Interview. Retrieved October 20, 2025.

    Open source URL
  5. [5]
    Esentire ContagiousInterview BeaverTail InvisibleFerret November 2024

    eSentire Threat Response Unit (TRU). (2024, November 14). Bored BeaverTail & InvisibleFerret Yacht Club – A Lazarus Lure Pt.2. Retrieved October 17, 2025.

    Open source URL
  6. [6]
    Socket Contagious Interview NPM April 2025

    Kirill Boychenko. (2025, April 4). Lazarus Expands Malicious npm Campaign: 11 New Packages Add Malware Loaders and Bitbucket Payloads. Retrieved October 20, 2025.

    Open source URL
  7. [7]
    Socket BeaverTail XORIndex HexEval Contagious Interview July 2025

    Kirill Boychenko. (2025, July 14). Contagious Interview Campaign Escalates With 67 Malicious npm Packages and New Malware Loader. Retrieved October 19, 2025.

    Open source URL
  8. [8]
    Socket HexEval BeaverTail Contagious Interview June 2025

    Kirill Boychenko. (2025, June 25). Another Wave: North Korean Contagious Interview Campaign Drops 35 New Malicious npm Packages. Retrieved October 19, 2025.

    Open source URL
  9. [9]
    ESET Contagious Interview BeaverTail InvisibleFerret February 2025

    Matej Havranek. (2025, February 20). DeceptiveDevelopment targets freelance developers. Retrieved October 17, 2025.

    Open source URL
  10. [10]
    Securonix Contagious Interview DEVPOPPER April 2024

    Securonix Threat Research, D.Iuzvyk, T. Peck, O.Kolesnikov. (2024, April 24). Analysis of DEV#POPPER: New Attack Campaign Targeting Software Developers Likely Associated With North Korean Threat Actors. Retrieved October 20, 2025.

    Open source URL
  11. [11]
    Zscaler ContagiousInterview BeaverTail InvisibleFerret November 2024

    Seongsu Park. (2024, November 4). From Pyongyang to Your Payroll: The Rise of North Korean Remote Workers in the West. Retrieved October 17, 2025.

    Open source URL
  12. [12]
    PaloAlto ContagiousInterview BeaverTail InvisibleFerret November 2023

    Unit 42. (2023, November 21). Hacking Employers and Seeking Employment: Two Job-Related Campaigns Bear Hallmarks of North Korean Threat Actors. Retrieved October 17, 2025.

    Open source URL
  13. [13]
    Datadog Security Labs Malicious PyPi Packages 2024

    Sebastian Obregoso and Christophe Tafani-Dereeper. (2024, May 23). Malicious PyPI packages targeting highly specific MacOS machines. Retrieved May 22, 2025.

    Open source URL
  14. [14]
    Datadog Security Labs Malicious PyPi Packages 2024

    Sebastian Obregoso and Christophe Tafani-Dereeper. (2024, May 23). Malicious PyPI packages targeting highly specific MacOS machines. Retrieved May 22, 2025.

    Open source URL
  15. [15]
    Fortinet Malicious NPM Packages 2023

    Jin Lee and Jenna Wang. (2023, October 2). Malicious Packages Hidden in NPM. Retrieved May 22, 2025.

    Open source URL
  16. [16]
    Fortinet Malicious NPM Packages 2023

    Jin Lee and Jenna Wang. (2023, October 2). Malicious Packages Hidden in NPM. Retrieved May 22, 2025.

    Open source URL
  17. [17]
    mitre-attackT1204.005
    Open source URL
  18. [18]
    mitre-attackT1204.005
    Open source URL
  19. [19]
    mitre-attackT1204.005
    Open source URL
  20. [20]
    ESET Contagious Interview BeaverTail InvisibleFerret February 2025

    Matej Havranek. (2025, February 20). DeceptiveDevelopment targets freelance developers. Retrieved October 17, 2025.

    Open source URL
  21. [21]
    Esentire ContagiousInterview BeaverTail InvisibleFerret November 2024

    eSentire Threat Response Unit (TRU). (2024, November 14). Bored BeaverTail & InvisibleFerret Yacht Club – A Lazarus Lure Pt.2. Retrieved October 17, 2025.

    Open source URL
  22. [22]
    PaloAlto ContagiousInterview BeaverTail InvisibleFerret November 2023

    Unit 42. (2023, November 21). Hacking Employers and Seeking Employment: Two Job-Related Campaigns Bear Hallmarks of North Korean Threat Actors. Retrieved October 17, 2025.

    Open source URL
  23. [23]
    Securonix Contagious Interview DEVPOPPER April 2024

    Securonix Threat Research, D.Iuzvyk, T. Peck, O.Kolesnikov. (2024, April 24). Analysis of DEV#POPPER: New Attack Campaign Targeting Software Developers Likely Associated With North Korean Threat Actors. Retrieved October 20, 2025.

    Open source URL
  24. [24]
    Sentinel One Contagious Interview ClickFix September 2025

    Aleksandar Milenkoski, Sreekar Madabushi, Kenneth Kinion. (2025, September 4). Contagious Interview | North Korean Threat Actors Reveal Plans and Ops by Abusing Cyber Intel Platforms. Retrieved October 20, 2025.

    Open source URL
  25. [25]
    Socket BeaverTail XORIndex HexEval Contagious Interview July 2025

    Kirill Boychenko. (2025, July 14). Contagious Interview Campaign Escalates With 67 Malicious npm Packages and New Malware Loader. Retrieved October 19, 2025.

    Open source URL
  26. [26]
    Socket Contagious Interview NPM April 2025

    Kirill Boychenko. (2025, April 4). Lazarus Expands Malicious npm Campaign: 11 New Packages Add Malware Loaders and Bitbucket Payloads. Retrieved October 20, 2025.

    Open source URL
  27. [27]
    Socket HexEval BeaverTail Contagious Interview June 2025

    Kirill Boychenko. (2025, June 25). Another Wave: North Korean Contagious Interview Campaign Drops 35 New Malicious npm Packages. Retrieved October 19, 2025.

    Open source URL
  28. [28]
    Validin Contagious Interview North Korea ClickFix January 2025

    Efstratios Lontzetidis. (2025, January 16). Lazarus APT: Techniques for Hunting Contagious Interview. Retrieved October 20, 2025.

    Open source URL
  29. [29]
    Zscaler ContagiousInterview BeaverTail InvisibleFerret November 2024

    Seongsu Park. (2024, November 4). From Pyongyang to Your Payroll: The Rise of North Korean Remote Workers in the West. Retrieved October 17, 2025.

    Open source URL
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