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MITRE ATT&CK® Technique

T1223: Compiled HTML File

Compiled HTML files (.chm) are commonly distributed as part of the Microsoft HTML Help system. CHM files are compressed compilations of various content such as HTML documents, images, and scripting/web related programming languages such VBA, JScript, Java, and ActiveX. [1] CHM content is displayed using underlying components of the Internet Explorer browser [2] loaded by the HTML Help executable program (hh.exe). [3]

Adversaries may abuse this technology to conceal malicious code. A custom CHM file containing embedded payloads could be delivered to a victim then triggered by User Execution. CHM execution may also bypass application whitelisting on older and/or unpatched systems that do not account for execution of binaries through hh.exe. [4] [5]

EnterpriseT1223TechniqueObject v1.2 Modified
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Historical object

This ATT&CK object is revoked or deprecated in the current MITRE ATT&CK release.

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Glexia's Take

Analyst summary pending validation

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Official MITRE ATT&CK definition

Compiled HTML File

Compiled HTML files (.chm) are commonly distributed as part of the Microsoft HTML Help system. CHM files are compressed compilations of various content such as HTML documents, images, and scripting/web related programming languages such VBA, JScript, Java, and ActiveX. [1] CHM content is displayed using underlying components of the Internet Explorer browser [2] loaded by the HTML Help executable program (hh.exe). [3]

Adversaries may abuse this technology to conceal malicious code. A custom CHM file containing embedded payloads could be delivered to a victim then triggered by User Execution. CHM execution may also bypass application whitelisting on older and/or unpatched systems that do not account for execution of binaries through hh.exe. [4] [5]

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
Domain ID Name Relationship / procedure
Enterprise T1218.001 Compiled HTML File Sub-technique This object revoked by Compiled HTML File.
Relationship explorer

All related ATT&CK context

revoked by · Technique T1218.001: Compiled HTML File 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
1.2
Created
Modified
Raw hash
bbea9b57a6f39e7b...
Imported snapshots across ATT&CK releases (1)
Release Bundle imported Object version Modified Status Raw hash
19.1 1.2 Current bundle Revoked bbea9b57a6f3…
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.

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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 HTML Help May 2018

    Microsoft. (2018, May 30). Microsoft HTML Help 1.4. Retrieved October 3, 2018.

    Open source URL
  2. [2]
    Microsoft HTML Help ActiveX

    Microsoft. (n.d.). HTML Help ActiveX Control Overview. Retrieved October 3, 2018.

    Open source URL
  3. [3]
    Microsoft HTML Help Executable Program

    Microsoft. (n.d.). About the HTML Help Executable Program. Retrieved October 3, 2018.

    Open source URL
  4. [4]
    MsitPros CHM Aug 2017

    Moe, O. (2017, August 13). Bypassing Device guard UMCI using CHM – CVE-2017-8625. Retrieved October 3, 2018.

    Open source URL
  5. [5]
    Microsoft CVE-2017-8625 Aug 2017

    Microsoft. (2017, August 8). CVE-2017-8625 - Internet Explorer Security Feature Bypass Vulnerability. Retrieved October 3, 2018.

    Open source URL
  6. [6]
    mitre-attack T1223
    Open source URL
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