HTML Application
By Contributors to Wikimedia projects
Published: 2006-11-29 · Archived: 2026-04-05 20:07:06 UTC
From Wikipedia, the free encyclopedia
This article is about Microsoft's proprietary HTA implementation. For information regarding the HTML5 Cache
Manifest, also referred to as offline HTML applications, see Cache manifest in HTML5.
HTML Application (HTA)
Filename extension .hta
Internet
media type
application/hta
Magic number %hta
Developed by Microsoft
Website
learn.microsoft.com/en-us/previous-versions/ms536471(v=vs.85)?
redirectedfrom=MSDN
An HTML Application (HTA) is a Microsoft Windows program whose source code consists of HTML, Dynamic
HTML, and one or more scripting languages supported by Internet Explorer, such as VBScript or JScript. HTML
is used to generate the user interface, and the scripting language is used for the program logic. An HTA executes
without the constraints of the web browser security model; in fact, it executes as a "fully trusted" application.
The usual file extension of an HTA is .hta .
The ability to execute HTAs was introduced to Microsoft Windows in 1999, along with the release of Microsoft
Internet Explorer 5.
[1]
 On December 9, 2003, this technology was patented.
[2][3]
HTAs give the developer the features of HTML together with the advantages of scripting languages. They are
popular with Microsoft system administrators who use them for system administration from prototypes to "full-scale" applications, especially where flexibility and speed of development are critical.[4]
https://en.wikipedia.org/wiki/HTML_Application
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One screenshot of one example window that is produced by mshta.exe
An HTA is executed using the program mshta.exe , or, alternatively, double-clicking on the file. This program is
typically installed along with Internet Explorer. mshta.exe executes the HTA by instantiating the Internet
Explorer rendering engine (mshtml) as well as any required language engines (such as vbscript.dll).
An HTA is treated like any executable file with extension .exe . When executed via mshta.exe (or if the file icon
is double-clicked), it runs immediately. When executed remotely via the browser, the user is asked once, before
the HTA is downloaded, whether or not to save or run the application; if saved, it can simply be run on demand
after that.[4]
By default, HTAs are rendered as per "standards-mode content in IE7 Standards mode and quirks mode content in
IE5 (Quirks) mode", but this can be altered using X-UA-Compatible headers.[4]
HTAs are dependent on the Trident (MSHTML) browser engine, used by Internet Explorer, but are not dependent
on the Internet Explorer application itself. If a user removes Internet Explorer from Windows, via the Control
Panel, the MSHTML engine remains and HTAs continue to work. HTAs continue to work in Windows 11 as well.
HTAs are fully supported running in modes equivalent to Internet Explorer versions 5 to 9. Further versions, such
as 10 and 11, still support HTAs though with some minor features turned off.[citation needed]
Security considerations
[edit]
When a regular HTML file is executed, the execution is confined to the security model of the web browser. This
means it is confined to communicating with the server, manipulating the page's object model (usually to validate
forms and/or create interesting visual effects) and reading or writing cookies.
On the other hand, an HTA runs as a fully trusted application and therefore has more privileges than a normal
HTML file; for example, an HTA can create, edit and remove files and registry entries. Although HTAs run in this
'trusted' environment, querying Active Directory can be subject to Internet Explorer Zone logic and associated
error messages.
To customize the appearance of an HTA, an optional tag hta:application was introduced to the HEAD section.
This tag exposes a set of attributes that enable control of border style, the program icon, etc., and provide
information such as the argument (command line) used to launch the HTA.[5] Otherwise, an HTA has the same
format as an HTML page.
https://en.wikipedia.org/wiki/HTML_Application
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---
title: HTA - Hello World
---
Any text editor can be used to create an HTA. Editors with special features for developing HTML applications
may be obtained from Microsoft[6] or from third-party sources.[7]
An existing HTML file (with file extension .htm or .html , for example) can be changed to an HTA by simply
changing the extension to .hta .
HTA files have been used to deliver malware.[8][9] One particular HTA, named 4chan.hta (detected by antiviruses
as JS/Chafpin.gen), was widely distributed by users of the 4chan imageboard as a steganographic image in which
the user was instructed to download this image as an HTA file, which when executed, would cause the computer
to automatically spam the website (evading 4chan's CAPTCHA in the process) with alternate variants of itself. It
was reported that such attacks were previously delivered in which the user was prompted to save it as a .js file.[10]
This is an example of Hello World as an HTML Application.

## HTA - Hello World

Adobe AIR
Active Scripting
Apache Cordova
Chromium Embedded Framework
Electron (software framework)
Firefox OS
React Native
XAML Browser Applications (XBAPs)
XUL and XULRunner - a language and environment for Mozilla cross-platform applications that resembles
the mechanism of HTML Applications.
Windows Script Host
1. ^ Article ID:200874 in Microsoft Support, in Microsoft Support Knowledge Base
2. ^ US6662341B1, Cooper, Phillip R.; Kohnfelder, Loren M. & Chavez, Roderick A., "Method and
apparatus for writing a windows application in HTML", issued 2003-12-09
3. ^ Festa, Paul (2003-12-10). "Microsoft wins HTML application patent". CNET. Archived from the original
on 2016-03-10. Retrieved 2016-01-10.
https://en.wikipedia.org/wiki/HTML_Application
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4. ^ Jump up to: a
 
b
 
c
 "Introduction to HTML Applications (HTAs)". Microsoft MSDN. May 2011. Retrieved
24 June 2016. Sections include Why Use HTAs, Creating an HTA, HTA-Specific Functionality, Security,
Compatibility, Deployment
5. ^ HTA:APPLICATION Object, in MSDN Library, the complete specification of the tag hta:application
6. ^ HTA Helpomatic
7. ^ HTAEdit, an editor for HTAs with a built-in debugger
8. ^ "Spora Ransomware Dropper Uses HTA to Infect System". VMRay. 2017-01-17. Retrieved 2018-12-22.
9. ^ "8 Scariest Ransomware Viruses". Retrieved 2018-12-22.
10. ^ Constantin, Lucian (2010-08-10). "4chan Flood Script Is Back with New Social Engineering Trick".
Softpedia. Retrieved 2021-11-09.
HTML Component (HTC) Reference at MSDN. An HTC encapsulates specific functionality or behavior
within HTAs.
The Script Center, The Script Center, home of Hey, Scripting Guy! Blog
Learn About Scripting for HTML Applications (HTAs), a tutorial site for learning about HTA's
Source: https://en.wikipedia.org/wiki/HTML_Application
https://en.wikipedia.org/wiki/HTML_Application
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