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List of common dangerous and malicious file extensions
These files are not dangerous by them self, but viruses and other malware often use these extensions to confuse and deceive the user to open them. Always recheck these files before you execute them.
Common possibly dangerous files may change in time as the popularity and significance of some formats can change.
Whole category of possibly dangerous files contains now 134 file types. Show all dangerous and malicious file types.
bat | Files with bat file extension can be commonly found as so called batch files. These text files are small scripts that contain a sequence of commands for a computer operating system. |
bin | Files with bin extension can also be found as various programs executables in Windows and Linux. |
chm | Files with chm extension are mainly related to Microsoft compiled HTML help file format. CHM is acronym for Compiled Help Modules. |
class | Files with class extension are mainly related to the Java programming language and used for compiled Java source codes known as Class bytecode files. |
com | Files with com extension can be generally found as command files. It is a type of program executable file format associated with the MS-DOS operating system. |
dll | Files with dll file extensions can be commonly found as dynamic link libraries for Microsoft Windows systems and apps. These files act as modules with additional runtime routines or data. |
drv | Files with drv extension are commonly found as device drives, especially in older versions of Windows operating system. Used for system purposes. |
exe | Files with exe extension are best known as main program executable files since the times of MS-DOS. It was adopted for executables in Windows as well. Executables are files that launch programs. |
jar | Files with jar extension are compressed archives, typically used for content in Java and distribution/installation purposes. |
js | Files with js extension can b commonly found as JavaScripts. Used to execute scripts on internet pages and such. |
lnk | File extension lnk is used for files that represent Windows shortcut to a program installed on computer. Every time you create a shortcut, a new lnk file acts as the actual link, which can be further customized with various settings such as launch parameters, icons, etc. Most lnk files are located on the user's Windows desktop. |
ocx | Files with ocx extension are associated with the Microsoft ActiveX Control items. An ocx is an OLE custom control (program) that is used by various Windows applications to provide such function as handling scroll bar movement and window resizing. |
pcx | Files with pcx file extension can be commonly found as bitmap pictures saved in old Paintbrush program. Can be opened in most modern graphic editors. |
scr | Files with scr extension can be most typically found as screensavers for Microsoft Windows operating system. However, never open random .scr files from untrustworthy sources. |
shs | Files with shs extension are quite often found as special OLE objects (scraps) from various Windows / MS Office apps. |
swf | Files with sw extension can be commonly found as Shockwave Flash movies in animated vector format, used mainly on Internet web sites. |
sys | Files with sys file extension can be often found as various system files in DOS / Windows and other operating systems. They contain information needed to properly load and configure operating system. A corrupted or missing system file can cause the system to be unstable or unable to boot. |
vbs | Files with vbs extension can be generally found as scripts made using Visual Basic programming language and development environment. Used in many programs. |
vxd | Files with vxd file extension can be mostly found as virtual device drivers from Microsoft Windows operating system. |
wmf | Files with wmf file extension can be found as pictures in Windows Metafile Format. WMF is a 16-bit format introduced in Windows 3.0; a newer 32-bit version with additional commands is called Enhanced Metafile (EMF). |
This is a list of some the most common file types from this category and may change in time as the popularity and significance of some formats can change. Whole category of possibly dangerous files contains now 134 file types. Show all dangerous and malicious files.