vx-underground
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The largest collection of malware source, samples, and papers on the internet.

Password: infected

https://vx-underground.org/
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Nerds online have identified a malware strain using "Deno", some fancy Javascript run-time thingy. I have no idea what this means. However, other malware nerds have identified this as unique.

The payload is a second stage which comes from a payload impersonating TopWebComics (???).

They're targeting WEB COMIC NERDS (or not, nobody really knows yet for sure). It was first identified by @malwrhunterteam

Cybersecurity vendor Cylerian identified a similar malware campaign using this exact malware technique in early January, 2026. This appears* to be a relatively novel malware campaign. Unfortunately, there is insufficient information to identify it more. It is difficult to ascertain for the time being if this is something truly unique or novel, or recycled stuff from a previous malware campaign.

tl;dr need to poke with stick. Not enough information. First glance looks interesting.

This payload is also interesting because it appears (at first glance) to contain mutation-like properties. When the first stage connects and downloads the second stage (in attached link is one of the mutated Javascript payloads), the code changes each time the loader connects to the URL. However, the core functionality (domains it connects to) seems* static.

tl;dr
Stage 1 - TopWebComicsv1.msi
Stage 2 - Weird URL, obfuscated Javascript payload
Stage 3 - ???
Stage 4 - Profit!!1

Stage 2 obfuscated Javascript changes each time it is downloaded, hence it's mutation characteristics.

Some researchers have identified the same weird URL it uses to delivery the Stage 2 payload as also hosting an Amadey panel. Amadey is a very common Malware-as-a-Service provider. However, it would be ... unusual ... for an obfuscated polymorphic multi-staged Javascript payload to delivery Amadey. It would be a ton of complexity and sophistication to then throw it all out of the window for some run-of-the-mill crimeware.

If you're a nerd who likes trying to reverse engineer obfuscated Javascript this is your time to shine because, as of this moment, nobody has de-obfuscated it or determined which malware campaign it is potentially associated.

Note: some of the obfuscation SUCKS. It's very clearly an information stealer. It targets cryptowallets, Discord (???), web browsers, etc.

tl;dr tl;dr crowdsourced malware reverse engineering for clout

https://gist.github.com/vxunderground/0d0c5f265d9f5248fa9dca171aec16ba
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> reverse engineer MalwareBytes
> find local sqlite db
> look inside
> password "VGhhbmtZb3VGb3JDaG9v"
> password: "c2luZ01hbHdhcmVieXRlcw"
> append
> base64
> decode
> "ThankYouForChoosingMalwarebytes"
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MalwareBytes has an local database on the machine. It is a SQLite database. It contains settings for various properties such as licensing, malware identified, and known-good and known-bad lists. This is standard anti-malware stuff. The database with "ThankYouForChoosingMalwarebytes" is the less interesting database, as it mostly contains settings (this can still be abused though).

Regardless, MalwareBytes does a couple of things with this SQLite stuff

MalwareBytes establishes a kernel-mode minifilter (mbam.sys). They setup minifilter callback routines to handle events on the system for process creation, process loading, and registry modification (Image 1)

In other words, MalwareBytes is notified immediately when a process is created or an executable image is loaded. When a process is created or an executable image is loaded, MalwareBytes has special functionality to temporarily "pause" execution so it can review it.

However, this "pause" happens faster than you or I can blink. Computers are fast.

The mbam.sys creates an internal record of all processes running. When a new process is loaded it is added to this internal record. When a program is closed, it is removed from the record. It does this so it doesn't accidentally review or "pause" the same process twice.

When a program is added to this list, the kernel-mode component communicates with the user-mode component that then signals and connects to a local SQLite database. The SQLite database then does a lookup to determine if the process "paused" is known or unknown (Image 2)

However, it should be noted, Image 2 is not the important SQLite instance I am looking for. This is something else MalwareBytes uses (and communicates to with kernel-mode components). The point still stands.

If it is known, it communicates back to the kernel-mode component that is it known. If it known, and known to be malicious, MalwareBytes takes action on the program attempting to run and immediately stops execution. If it is known to be good, MalwareBytes marks it internally as "seen" and keeps it in it's internal record.

Image 3 is from the internal database they use. It's fairly large and is mostly settings. I still haven't find where the really nice, big, and important dataset they use is. It requires more poking and more sticks.
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Going to do a write-up on poking MalwareBytes with a stick, how it works fundamentally, some possible attack vectors against it, ... then I'll do something else.

If you have any recommendations on what I should poke with a stick please let me know.
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Hello,

We have hit a significant milestone. 400,000 followers.

What does this mean? I've got 400,000 little people inside of my internet. I don't know how so many tiny people got in here, but you're in there.

Thank you for the love and support. If any of you by chance happen to be extremely wealthy please consider giving me a large quantity of money so I don't have to do work.

I would love having a large quantity of money.

Mildly interesting things about this accounts followers:

- Some of you are sex workers. Is this surprising that sex workers are on the internet? No. Is it surprising sex workers are interested in malware? Kind of. I'm aware some of the sex workers following this account are very famous and it surprised me.

- Some of you are employed by the United States government. I'm well aware some of you are employed by the FBI or NSA. It is very strange receiving a $5 monthly reoccurring donation from someone employed by the NSA. I'll take your money still.

- Some of you work for governments outside the United States. It is interesting receiving emails from foreign militaries asking about particular malware samples. It is also surprising some of you email me (unironically) from your military emails.

- Some of you are criminals. Yes, I see your emails and messages. I see you're ransoming places, developing ransomware, or extorting people. I speak with criminals less now because I have a baby boy and I don't want him to grow up thinking Daddy is an internet schizo

- Some of you are regular people who do regular stuff. I see you commenting and being curious about stuff. It's surprising seeing teachers, or students, or local politicians, or geologists, or firefighters, or athletes, talking to me about malware. Once again, is it surprising normal people are on the internet? No. Is it interesting to see a random ass person curious about malware? Kind of. I enjoy it.

- Some of are unironically professional video game players. If I ever want to be carried in a video game I WILL call in a favor.

- Some of you work for cool companies. I'm always delighted to get contacted by a company like Rockstar Games, or NVIDIA, or Walmart (unironically).

- Some of you are dead. I've lost several friends, peers, and colleagues since vx-underground was created. Sometimes I look at your accounts, scroll your post history, and feel sad.

Lots of cool people doing cool stuff. I appreciate the love and support over the past 6.5 years.

Cheers,
- smelly smellington
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mY tEsLa iS sElF dRiViNg

This is ancient technology. Nothing new. My Dad's 94 Toyota had self driving capabilities.

It was called "cruise control".

All you did was flip the switch and then let Jesus take the wheel.

Sometimes we ran over pedestrians, drove on the sidewalk, sped through red lights, but God dammit it WORKED. We didn't need any "government" telling us how to cruise
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I remember when Bitcoin first appeared.

I thought, "cryptocurrency seems like made up internet money."

Fast forward, it's the year 2026. I think, "cryptocurrency seems like made up internet money."
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I have continued to poke MalwareBytes with a stick. I've written a little article about it.

I discuss their main executable, some of their minifilter stuff, their proprietary file format ... I haven't even scratched the surface. I am TIRED

https://malwaresourcecode.com/home/my-projects/write-ups/malwarebytes-internals-incomplete
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vx-underground
I have continued to poke MalwareBytes with a stick. I've written a little article about it. I discuss their main executable, some of their minifilter stuff, their proprietary file format ... I haven't even scratched the surface. I am TIRED https://malwa…
There is so much to reverse with their "SwissKnife", internal COM stuff, their internal protocol, their VPN technology, their hooking mechanisms.

I don't know if I got that dog in me to finish this. It's really interesting, but I want to do something else now.
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One of my biggest weaknesses is writing. I hate writing.

My cybersecurity peers, colleagues, friends, who have the willpower to sit down and write and explain their work (or discoveries) is truly amazing.

I'd argue the process of writing is actually more difficult than the actual reverse engineering and/or development part. Partially because it's really boring, partially because it requires you to put structure and coherency on the madness floating around in your brain.

Huge shout-out to the nerds who have written big ass blog posts (or books).
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Discussion on the internet today on the origins of traffic on the highway and the accordion effect it produces.

People were critical toward others who intentionally slowed down to be "nosey" about car accidents.

Let me be totally clear: I am one of those people.

I want to see the aftermath of a violent car accident. I am curious who is involved. I want to see a dead body. I 100% will slow down and take my time to inspect the scene. If possible, I will take out my phone and try to record it so I can show my friends later.
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