These Files Don't Show Their Extension

[@_JohnHammond]

wowzer bowser anyway if you're into this kind of stuff, check out jh.live/training and sign up for my newsletter at jh.live/newsletter for more

[@martink.7497]

Fun fact with the compression algorithms. [32:21] Depending on the type and input, some can result indeed bigger instead of smaller. Imagine a simple example with text content "AAAAAA" where you compress it and the result is "6A". As you can see, it is smaller, right - but what if the content will be "ABC"? The result will be "1A1B1C" resulting twice as big, instead of smaller. That is also the reason why there are multiple compression algorithms and where one can shine, the other fails and otherwise.

[@teamredstudio7012]

I believe one of the reasons it's larger often for very small files is the metadata. I experienced this phenomenon while writing my own compression algorithm one day. The metadata might not go smaller than a certain size and this size depends on the file metadata structure. For example, a plaintext file might only contain 5 UTF-8 characters and be 5 bytes, but when archived, the archive contains the modification date, creation date, file path and the compressed data so it will always be larger than the input 5 bytes. It also depends on the entropy of the input file, the compression algorithm doesn't make all files smaller, only low entropy files are shrunk, high entropy files are actually compressed larger than their input because there is only a finite amount of possible byte combinations.

[@chri-k]

Any lossless compression algorithm must on average of all possible inputs compress by a factor less than or equal to 1 ( so, either not at all or increase the size ) Otherwise you'd be storing more than 1 bit of information in each bit of the file

[@olnnn]

@@teamredstudio7012 Compression algorithms will usually fall back to leaving a block of data uncompressed if it ends up being larger when compressed but it will still result in some small overhead in the datastream or file format compared to the original file since it has to actually store some metadata about compression method and size etc

[@teamredstudio7012]

@@olnnn That is correct, I even implemented that in my own algorithm, where if the compressed chunk including the header for this chunk is larger than the uncompressed data the original data is just copied.

[@BillAnt]

Oh man I was hoping for the NTAuthority\System will be able to edit/delete, but now I can't wait for the TrustedInstaller video. John Hammond to the rescue, that should be juicy. :D

[@peekachugaming3231]

You can create .url files simply by creating a normal .lnk file over the GUI and simply paste in a URL. It will create a Internet-Shortcut (.url)-File - Steam does use those for theyre game shortcuts for example. Also you can refresh any explorer.exe content or your desktop with F5.

[@whtiequillBj]

@28:37, actually game shortcuts made by Steam are .url files not .lnk.

[@teamredstudio7012]

Knowing where they are stored now, I might just make a little powershell script that scans the registry for all files with hidden extensions to make sure there aren't any extra.

[@BillAnt]

Also delete the NeverShowExt keys from all instances. ;)

[@Bizzybugproductions]

​@@BillAnt can you help me understand this statement?

[@BillAnt]

@@Bizzybugproductions - Watch the full video to understand it.

[@teamredstudio7012]

btw, if you want the script, I posted it in a second comment.

[@pinkerdroit]

Cheers! Thank you for covering this. 😃👍💛

[@DanGood122]

FYI, you can right click the desktop to refresh it and the changes will take effect.

[@peekachugaming3231]

Actually can press F5 to refresh on the desktop/explorer.

[@BillAnt]

A simple desktop refresh via F5 or right click will not show the extensions via the removal of the NeverShowExt key. He ran a script which contains "taskkill /F /IM explorer.exe" and "start explorer.exe".

[@superb3333yt]

So .DeskLink, .MAPImail, .mydocs and .zfsendtotarget aren't supposed to contain anything. If you drag and drop a file onto them, they will do their action. Windows uses them in the SendTo context menu, so there naturally in the %appdata%\Roaming\Microsoft\Windows\SendTo folder

[@vpakarinen]

This was very good to learn, thank you John.

[@Eskimostyle]

What main operating system do you use @John? Is it like bare metal ubuntu and all the security stuff you do is on VM's or some other kind of setup? Thank you in advance!

[@revenevan11]

I'm also curious what his daily driver OS is! I get that he always spins up a VM with Kali or Remnux to actually work in during these videos, or a windows VM to test something in... but from what OS does he do all that? (Some flavor of Linux, but which?) & is that the same main OS he uses personally outside of recording vids, too?

[@raymondcarlson7836]

The Moles (Minecraft hacker guys) used the .pif trick in a campaign against Minehut. They used .pif to trick users into running a stealer under the guise of it being a captcha image.

[@CityNaturePig]

15:20 Your Desktop, Documents and some other folders on the side are already such libraries in Win11. Maybe you cannot add a library to a library. Or Win11 is just being weird.

[@msh6610]

Allmost fell for a lnk file inside an archive that looked like a folder few years ago.. It wanted todo some powershell stuff from an url... Pretty sniky :s

[@Lampe2020]

Isn't there a NirSoft tool that allows you to run any executable or command as any user with basically any settings you can imagine?

[@logiciananimal]

Calculator has a protocol handler? Wild. I had looked at protocol handlers briefly based on one of JH (or maybe it was LiveOverflow)'s stuff and seemingly missed that one! (I remember writing code to enumerate all the registered ones.)

[@svinxt]

Where do you get your Virtual Machines from?

[@ThatGuySnagz]

Hey John, what keyboard do you use?

[@VaibhavShewale]

ooh man this are some awesome extension

[@elderdragon7856]

4:53 not working when I do this. It is still showing the ending

[@Datalata]

Super interesting as always!

[@jmr]

I vaguely remember something about setting the hot key but I don't believe it was saved in the file.

[@Xeno881]

I want learn Format String Vulnerability in pwn to get shell,can you teach me?

[@harbiyeli35]

Do you suggest upgrading from windows 10 to 11?

[@Y0GAAAA]

Very nice video, we want the following 👽

[@KyleRice]

How did John Get the Checkmarks

[@sunla]

The emojis? You can pull that up on Windows with a key

[@DanGood122]

Ctrl + : for emoji menu within Windows

[@KyleRice]

Thanks for the info

[@kipchickensout]

We have software which works with MAPI or SMTP depending on the config so I guess it's actually used

[@Neuer_Alias_erstellen]

cool shirt

[@luketurner314]

For anyone wondering how John is 'typing' emoji in Windows: windows/super-key + . (period/full stop)

[@Jonathan-d2g]

This is why you use Linux.

[@NyaryanUwUrrior]

GNU/Linux🤓🤓 😤😤☝☝🤬🤬🤬👹👹

[@muizzsiddique]

Ah yes, the Operting System that stores plain text files, binary executables, and literally anything else, all in a file with no file extension.

[@CartoonSlug]

​@@muizzsiddique Oh ok ill just use windows

[@benebene9525]

​@@muizzsiddiqueYou do realize that nobody is stopping you from using extensions anyway? The point is that linux doesnt lie to the user about filenames

[@wild_elliot]

​​Everything has it's own pros and cons​@@muizzsiddique

[@Ruhgtfo]

Memories bring back memories bring back YO😂

[@666KoXz666]

total commander shows every extention

[@omahanprabla3058]

Hope you're not using the cracked version bro

[@codyaimes4354]

Lol. I spent a few hours last weekend doing something similar.

[@270jonp]

quality video.

[@jabelltulsa]

Dude ... pif files .... I know them. I'm so old.

[@dj_chateau]

Completely vanilla; opens Sublime. 😂

[@sophisticatedserpent1512]

chat jibbity 🤣

[@edwardkostreski6733]

That .mapi sounds like a pandoras box 😂

[@granitium]

I think search-ms failed because you typed 'johnh' instead of 'john'

[@MrKrezol]

.url icon worked in Internet explorer

[@Ormaaj]

Is there really no way to show the .lnk? A problem is that they look exactly like symlinks except that the "link target" field is empty, which you can't always see, so that's kind of annoying.

[@ToastExists]

That's why I use Linux

[@BigFunnyGiant]

Windows still can have PIF files? What?

[@gaatjenietsaan88]

I got hacked by a sketch software pls help me

[@gaatjenietsaan88]

It says i need to pay 1500 in bitcoin

[@paulbond8244]

🔥🔥🔥

[@MrJohnsoncomputerscientist]

First comment from Kenya always inspired.

[@munchcup]

Usituhack banah

[@Wwinstar]

No views?! Never been so early on a video.

[@haxxor7606]

This guy does not do segways. Like this segway to our sponsor...

[@chri-k]

Segue

[@IDaVinceE]

Nope, but this guy segways... Like he is on a roll.

[@Mudflap1110]

Don't use windows

[@new_simsons]

Cry about it

[@BigFunnyGiant]

Some people really don’t have a choice. They have to for certain software or for work.

[@JohnSmith-jc7dk]

Linux GUI is very buggy

[@كرةالمحترفين-ت2ث]

one of pest in my life

[@ThisIsJustADrillBit]

FIRST ❤ Also you're the man 🔥 🤘

[@adrian18ftw]

oh okey new thing for me to use ...

[@soft_compound]

mate how am i so early

[@L3GiÓNsec]

First

[@AltaBross]

Big fan sir i watched you every video they are awesome how can i contact you online or chat with you i have some cybersecurtiy or security related question from which platform i can ask you that questions?