clamav VS file

My recommendation would be to use ClamAV an open source antivirus engine. It is a versatile tool designed to detect multiple types of threats from numerous file formats and other use cases (cross-platform, integration such as mail server). Finally, it is updated on a daily basis, ensuring protection against the latest known threats. This rapid update cycle is crucial for an antivirus tool to be effective.

Linux has (free) tools to improve security and detect/remove malware: Lynis,Chkrootkit,Rkhunter,ClamAV,Vuls,LMD,radare2,Yara,ntopng,maltrail,Snort,Suricata...

There's clamAV which is open source: https://www.clamav.net/

For personal use, the most commonly used is ClamAV.

Absolutely but if the OP feels they must then they should look into the free ClamAV.

I'd go with what Bman said but second to that ClamAV is a good free option.

Ehhh, there is antivirus software for Linux, like ClamAV. Also a lot of exploits these days target browsers since its an easier attack vector. Also, malware is malware, and most servers use Linux by default. So any malware that's targeting a Linux server could target a desktop user. I don't like the whole "Haha, malware doesn't affect me because everyone targets windows". Sure, those "download now!" buttons that are targeted to gullible windows users might not work on your operating system however your OS is still vulnerable and can still be exploited by malware.

https://www.darwinsys.com/file/

This is the authors website. Apparently yeah its not part of GNU utils, I had no idea, I knew it came with most Linux systems so I looked for the Debian package and found the site linked above.

https://packages.debian.org/bookworm/file

https://github.com/file/file/blob/master/magic/Magdir/gentoo https://www.iana.org/assignments/media-types/application/vnd.gentoo.ebuild (among others)

Look into libmagic.

in installations of Linux, file is a command to retrieve some basic information about a file type. Because contrasting to the organization of Windows, the file extension in Linux can be less important for the file's use (even irrelevant), than the actual content.

In this case, it's hitting this set of rules. I would guess it hits both class and public.

But I don't think this is what you meant. I think your question is something more like: how many file formats are there? The Unix file command recognizes several thousand, and Wikipedia has a list. Of course these are only the most common, and it's hard to delineate what counts as a unique file format. (Is YAML one file format or millions?)

The magic number for all ogg files is the same (OggS) and files magic file looks like it decides the mime type based on the codecs used in the file. However, it looks like application/ogg is used only if the file contains Kate (Karaoke and Text) content.

Also the magic number database for guessing the format of a file:

https://www.darwinsys.com/file/