On October 20, a hacker who calls themselves Dark X said they logged in to a server and stole the personal data of 350 million Hot Topic customers. The following day, Dark X listed the data, including alleged emails, addresses, phone numbers, and partial credit card numbers, for sale on an underground forum. The day after that, Dark X said Hot Topic kicked them out.

Dark X told me that the apparent breach, which is possibly the largest hack of a consumer retailer ever, was partly due to luck. They just happened to get login credentials from a developer who had access to Hot Topic’s crown jewels. To prove it, Dark X sent me the developer’s login credentials for Snowflake, a data warehousing tool that hackers have repeatedly targeted recently. Alon Gal from cybersecurity firm Hudson Rock, which first found the link between infostealers and the Hot Topic breach, said he was sent the same set of credentials by the hacker.

The luck part is true. But the claimed Hot Topic hack is also the latest breach directly connected to a sprawling underground industry that has made hacking some of the most important companies in the world child’s play.

AT&T. Ticketmaster. Santander Bank. Neiman Marcus. Electronic Arts. These were not entirely isolated incidents. Instead, they were all hacked thanks to “infostealers,” a type of malware that is designed to pillage passwords and cookies stored in the victim’s browser. In turn, infostealers have given birth to a complex ecosystem that has been allowed to grow in the shadows and where criminals fulfill different roles. There are Russian malware coders continually updating their code; teams of professionals who use glitzy advertising to hire contractors to spread the malware across YouTube, TikTok, or GitHub; and English-speaking teenagers on the other side of the world who then use the harvested credentials to break into corporations. At the end of October, a collaboration of law enforcement agencies announced an operation against two of the world’s most prevalent stealers. But the market has been able to grow and mature so much that now law enforcement action against even one part of it is unlikely to make any lasting dent in the spread of infostealers.

Based on interviews with malware developers, hackers who use the stolen credentials, and a review of manuals that tell new recruits how to spread the malware, 404 Media has mapped out this industry. Its end result is that a download of an innocent-looking piece of software by a single person can lead to a data breach at a multibillion-dollar company, putting Google and other tech giants in an ever-escalating cat-and-mouse game with the malware developers to keep people and companies safe.

“We are professionals in our field and will continue to work on bypassing future Google updates,” an administrator for LummaC2, one of the most popular pieces of infostealer malware, told me in an online chat. “It takes some time, but we have all the resources and knowledge to continue the fight against Chrome.”

The Stealers

The infostealer ecosystem starts with the malware itself. Dozens of these exist, with names like Nexus, Aurora, META, and Raccoon. The most widespread infostealer at the moment is one called RedLine, according to cybersecurity firm Recorded Future. Having a prepackaged piece of malware also dramatically lowers the barrier to entry for a budding new hacker. The administrator of LummaC2, which Recorded Future says is in the top 10 of infostealers, said it welcomes both beginner and experienced hackers.

Initially, many of these developers were interested in stealing credentials or keys related to cryptocurrency wallets. Armed with those, hackers could empty a victim’s digital wallets and make a quick buck. Many today still market their tools as being able to steal bitcoin and have even introduced OCR to detect seed phrases in images. But recently those same developers and their associates figured out that all of the other stuff stored in a browser—passwords to the victim’s place of work, for example—could generate a secondary stream of revenue.

“Malware developers and their clients have realized that personal and corporate credentials, such as login details for online accounts, financial data, and other sensitive information, hold substantial value on the black market,” RussianPanda, an independent security researcher who follows infostealers closely, told 404 Media. Infostealer creators pivoted to capture this information too, she said. In essence, the exhaust from cryptocurrency-focused heists has created an entire new industry in its own right that is causing even more destruction across healthcare, tech, and other industries.

Some stealers then sell these collected credentials and cookies, or logs, themselves via bots on Telegram. Telegram, rather than acting as simply a messaging app, provides critical infrastructure for these teams. The entire process from buying to selling stolen logs is automated through Telegram bots. Telegram did not respond to a request for comment.

Infostealers are not especially hard to write, but the malware developers constantly butt heads with engineers inside tech giants, such as Google, who are trying to stop them from stealing users’ credentials.

In July, for example, Google Chrome rolled out an update that was designed to lock applications other than Chrome—including malware—from accessing cookie data. For a moment, Chrome had the upper hand. LummaC2 gave its users some workarounds, but none were a reliable fix. Some malware developers make their grievances known more explicitly. In one update, a pair of infostealers included the phrase “ChromeFuckNewCookies” in their malware’s code.

“It’s a little bit of a cat and mouse, but we think that this is a game that we want to play as much as we can if the outcomes remain positive,” Will Harris, staff software engineer on Google Chrome, said. “We want to protect users, obviously, as much as we can.” That doesn’t just come in securing Chrome itself and protecting more data from infostealers. It also includes “disruption,” such as more researchers writing about infostealers’ particular techniques, which in turn constrains the tools available to the malware developers. Releasing updates one by one on a regular basis, rather than all at once, can also disrupt the malware developers. Instead of the criminal coders knowing what they need to fix all in one go, they can never be quite sure what Google is going to clamp down on next, wasting more of their time.

After one update, a lot of the customers of a stealer were “extremely upset, and they [the malware makers] had to work nights on coming up with a bypass,” Harris said. He added that one stealer, called Vidar, increased the cost of its tool too. “We have to stay agile here. I mean the infostealers are moving fast on this as well, and we want to be keeping up with them, and I think we are able to in this case,” he said.

He also pointed specifically to Microsoft Windows. “When you compare Windows with, say, Android, or with ChromeOS, or even macOS, those platforms have this strong application isolation.” Meaning, that malware has a harder time stealing data from other parts of the system. “We noticed on Windows, which was obviously a major platform for us, that these protections didn’t exist.”

In an email, a Microsoft spokesperson said, “In addition to the hardware-backed baseline requirements for all Windows PCs—such as, TPM, Secure Boot, and virtualization-based security, there are many security features now enabled by default in Win11 which makes it more difficult for info-stealers. Our guidance is that users should run as Standard User and not Admin on their Windows device. Running standard user means users (and apps being used by users) can make changes to their computer but do not have full system access by default, so that info stealers will not have the full access required to make it easy to steal the data that they are after.”

Infostealer malware for Mac does exist, but to a much smaller degree, according to Recorded Future.

A malware creator may have an effective piece of software in their hands. But ultimately getting that software onto victims’ computers is the job of someone else.

The Traffers

With electronic rap music playing in the background, a man stretches his hands forward and leans back into a chair. The camera pans around their alleged apartment: huge floor-to-ceiling windows in a large dining room, wood-paneled floors, and a funky chandelier. In another shot the man opens a laptop, types away, and then takes a sip of what looks like whiskey. The implication: This could be you if we work together.

This is one of a dizzying number of adverts on an underground forum called Lolz where “traffers” gather to look for new recruits. In this case, the man in the video is looking for people to push a fake casino tool that can steal people’s funds. But much of the rest of the “traffers” section is dedicated to proliferating infostealers. The job of these contractors is to help spread the malware or get them traffic, with teams vying for attention in a crowded marketplace. Each tries to one-up the other with outrageous advertising and branding. They use names such as “Billionaire Boys Club,” “Baphomet,” and “Chemodan.” Their adverts include animated GIFs of computer-generated luxury cars or private jets. Another for “Cryptoland Team” shows a knight in armor looking down at a skeleton in a hood writing on parchment paper. Cryptoland Team say they work with LummaC2 and another stealer called Rhadamanthys.

“Payment by logs or money. We give you a choice: Either you take the logs, or we buy them,” one advert from a team called Baphomet, with satanic branding, says.

Each lists the brand of infostealer they use, what split of the profits a collaborator can expect, and whether they allow an associate to take any extra exfiltrated logs. And most explicitly say that anyone they work with is prohibited from targeting the Commonwealth of Independent States (СНГ), or former members of the Soviet Union, which includes Belarus, Ukraine, and Russia. Collaborators then leave reviews and screenshots proving they’ve made money working with the team.

Many of these teams take new applications via their own Telegram bots. Some are strict in that they only want to work with people who are already experienced, while others seemingly take anyone on board. 404 Media was able to easily pass an application process for two traffer teams by answering some basic questions. After that, the bots sent links to the teams’ respective manuals, which lay out how to spread the malware.

One manual from Baphomet, for example, recommends bundling the stealer into cheating software for Roblox. It then describes how to set up a YouTube video advertising the cheat, and by extension, help propagate the malware.

Another advert from a traffer team says it works with TikTok, Telegram, Instagram, Twitter, Facebook, YouTube, YouTube Shorts, email newsletters, bloggers, and influencers. In the video of the hacker drinking whiskey, at one point his laptop shows a page on TikTok. Many of the manuals reflect this and recommend distributing infostealers via other social media sites or point to GitHub as an effective trafficking method.

Some infostealers are also hidden inside cracked or pirated software. One reason they’re so effective is that users are seeking the software out, not the other way around. People are actively searching for free software, be damned about the consequences.

A Google spokesperson said in an email, “We have policies in place to prevent spam, scams, or other deceptive practices that take advantage of the YouTube community. This includes prohibiting content where the main purpose is to trick others into leaving YouTube for another site.”

Meta did not respond to a request for comment. TikTok acknowledged a request but did not provide a response in time for publication.

And these traffers and others are clearly successful on a massive scale. Recorded Future says it sees 250,000 new infostealer infections every day.

The Channels and Sites

The harvested credentials are then fed into Telegram channels, where a tsunami of cookies and logins are available for purchase. The administrator for LummaC2 told me “This brings us good income, but I am not ready to disclose specific amounts,” referring to selling the stolen logs. Testing out the Telegram bot, it’s possible to filter by country, the number of cookies, or passwords available. 404 Media saw many U.S. logs available for sale. Over the past few weeks, some of these Telegram channels have been deleted. Telegram did not respond to a request for comment asking if it had taken action against them.

These, in turn, have their own branding, much like the traffers. Many channels also distribute stolen credentials for free, likely in an attempt to advertise their paid offerings. Even the freely available credentials can be devastating for a targeted organization. Earlier this year, a security researcher used exposed logins to compromise a server belonging to AU10TIX, an identity verification company that works with TikTok, Uber, and X. Those credentials came from a free stream available on Telegram, the researcher showed 404 Media at the time.

Some websites are also dedicated to, or have sections for, selling infostealer logs. Genesis Market is a site where the hackers responsible for the 2021 breach of Electronic Arts sourced a login token for the company’s Slack. In 2023, authorities shut down Genesis Market. But much of the credential selling has moved over to another long-running site, Russian Market, according to Recorded Future.

And this is where the hackers come in. Judische, the hacker linked to breaches at AT&T, Ticketmaster, and other companies that used Snowflake, likely lifted stolen credentials from these sorts of feeds and then used those to log into target servers. In some instances, those companies were not using multifactor authentication. But the power of logs is that they can sometimes bypass that extra layer of protection—a cookie can trick a service into thinking the user is trusted, and not prompt them for an extra login code.

Potentially with no idea how the logs were ultimately sourced, some English hackers ask in large group chats for passwords related to targets in particular countries. One I recently saw said they wanted logs for Canadian victims.

When interviewing Dark X, the alleged Hot Topic hacker, they seemed to sense another potential way to make some money. They mentioned they also sell logs.

“You wanna buy? haha,” they wrote.