Who Got Arrested in the Raid on the XSS Crime Forum?

On July 22, 2025, the European police agency Europol said a long-running investigation led by the French Police resulted in the arrest of a 38-year-old administrator of XSS, a Russian-language cybercrime forum with more than 50,000 members. The action has triggered an ongoing frenzy of speculation and panic among XSS denizens about the identity of the unnamed suspect, but the consensus is that he is a pivotal figure in the crime forum scene who goes by the hacker handle “Toha.” Here’s a deep dive on what’s knowable about Toha, and a short stab at who got nabbed.

Europol did not name the accused, but published partially obscured photos of him from the raid on his residence in Kiev. The police agency said the suspect acted as a trusted third party — arbitrating disputes between criminals — and guaranteeing the security of transactions on XSS. A statement from Ukraine’s SBU security service said XSS counted among its members many cybercriminals from various ransomware groups, including REvil, LockBit, Conti, and Qiliin.

Since the Europol announcement, the XSS forum resurfaced at a new address on the deep web (reachable only via the anonymity network Tor). But from reviewing the recent posts, there appears to be little consensus among longtime members about the identity of the now-detained XSS administrator.

The most frequent comment regarding the arrest was a message of solidarity and support for Toha, the handle chosen by the longtime administrator of XSS and several other major Russian forums. Toha’s accounts on other forums have been silent since the raid.

Europol said the suspect has enjoyed a nearly 20-year career in cybercrime, which roughly lines up with Toha’s history. In 2005, Toha was a founding member of the Russian-speaking forum Hack-All. That is, until it got massively hacked a few months after its debut. In 2006, Toha rebranded the forum to exploit[.]in, which would go on to draw tens of thousands of members, including an eventual Who’s-Who of wanted cybercriminals.

Toha announced in 2018 that he was selling the Exploit forum, prompting rampant speculation on the forums that the buyer was secretly a Russian or Ukrainian government entity or front person. However, those suspicions were unsupported by evidence, and Toha vehemently denied the forum had been given over to authorities.

One of the oldest Russian-language cybercrime forums was DaMaGeLaB, which operated from 2004 to 2017, when its administrator “Ar3s” was arrested. In 2018, a partial backup of the DaMaGeLaB forum was reincarnated as xss[.]is, with Toha as its stated administrator.

CROSS-SITE GRIFTING

Clues about Toha’s early presence on the Internet — from ~2004 to 2010 — are available in the archives of Intel 471, a cyber intelligence firm that tracks forum activity. Intel 471 shows Toha used the same email address across multiple forum accounts, including at Exploit, Antichat, Carder[.]su and inattack[.]ru.

DomainTools.com finds Toha’s email address — toschka2003@yandex.ru — was used to register at least a dozen domain names — most of them from the mid- to late 2000s. Apart from exploit[.]in and a domain called ixyq[.]com, the other domains registered to that email address end in .ua, the top-level domain for Ukraine (e.g. deleted.org[.]ua, lj.com[.]ua, and blogspot.org[.]ua).

Nearly all of the domains registered to toschka2003@yandex.ru contain the name Anton Medvedovskiy in the registration records, except for the aforementioned ixyq[.]com, which is registered to the name Yuriy Avdeev in Moscow.

This Avdeev surname came up in a lengthy conversation with Lockbitsupp, the leader of the rapacious and destructive ransomware affiliate group Lockbit. The conversation took place in February 2024, when Lockbitsupp asked for help identifying Toha’s real-life identity.

Lockbitsupp didn’t share why he wanted Toha’s details, but he maintained that Toha’s real name was Anton Avdeev. I declined to help Lockbitsupp in whatever revenge he was planning on Toha, but his question made me curious to look deeper.

It appears Lockbitsupp’s query was based on a now-deleted Twitter post from 2022, when a user by the name “3xp0rt” asserted that Toha was a Russian man named Anton Viktorovich Avdeev, born October 27, 1983.

Searching the web for Toha’s email address toschka2003@yandex.ru reveals a 2010 sales thread on the forum bmwclub.ru where a user named Honeypo was selling a 2007 BMW X5. The ad listed the contact person as Anton Avdeev and gave the contact phone number 9588693.

A search on the phone number 9588693 in the breach tracking service Constella Intelligence finds plenty of official Russian government records with this number, date of birth and the name Anton Viktorovich Avdeev. For example, hacked Russian government records show this person has a Russian tax ID and SIN (Social Security number), and that they were flagged for traffic violations on several occasions by Moscow police; in 2004, 2006, 2009, and 2014.

Astute readers may have noticed by now that the ages of Mr. Avdeev (41) and the XSS admin arrested this month (38) are a bit off. This would seem to suggest that the person arrested is someone other than Mr. Avdeev, who did not respond to requests for comment.

A FLY ON THE WALL

For further insight on this question, KrebsOnSecurity sought comments from Sergeii Vovnenko, a former cybercriminal from Ukraine who now works at the security startup paranoidlab.com. I reached out to Vovnenko because for several years beginning around 2010 he was the owner and operator of thesecure[.]biz, an encrypted “Jabber” instant messaging server that Europol said was operated by the suspect arrested in Kiev. Thesecure[.]biz grew quite popular among many of the top Russian-speaking cybercriminals because it scrupulously kept few records of its users’ activity, and its administrator was always a trusted member of the community.

The reason I know this historic tidbit is that in 2013, Vovnenko — using the hacker nicknames “Fly,” and “Flycracker” — hatched a plan to have a gram of heroin purchased off of the Silk Road darknet market and shipped to our home in Northern Virginia. The scheme was to spoof a call from one of our neighbors to the local police, saying this guy Krebs down the street was a druggie who was having narcotics delivered to his home.

I happened to be lurking on Flycracker’s private cybercrime forum when his heroin-framing plan was carried out, and called the police myself before the smack eventually arrived in the U.S. Mail. Vovnenko was later arrested for unrelated cybercrime activities, extradited to the United States, convicted, and deported after a 16-month stay in the U.S. prison system [on several occasions, he has expressed heartfelt apologies for the incident, and we have since buried the hatchet].

Vovnenko said he purchased a device for cloning credit cards from Toha in 2009, and that Toha shipped the item from Russia. Vovnenko explained that he (Flycracker) was the owner and operator of thesecure[.]biz from 2010 until his arrest in 2014.

Vovnenko believes thesecure[.]biz was stolen while he was in jail, either by Toha and/or an XSS administrator who went by the nicknames N0klos and Sonic.

“When I was in jail, [the] admin of xss.is stole that domain, or probably N0klos bought XSS from Toha or vice versa,” Vovnenko said of the Jabber domain. “Nobody from [the forums] spoke with me after my jailtime, so I can only guess what really happened.”

N0klos was the owner and administrator of an early Russian-language cybercrime forum known as Darklife[.]ws. However, N0kl0s also appears to be a lifelong Russian resident, and in any case seems to have vanished from Russian cybercrime forums several years ago.

Asked whether he believes Toha was the XSS administrator who was arrested this month in Ukraine, Vovnenko maintained that Toha is Russian, and that “the French cops took the wrong guy.”

WHO IS TOHA?

So who did the Ukrainian police arrest in response to the investigation by the French authorities? It seems plausible that the BMW ad invoking Toha’s email address and the name and phone number of a Russian citizen was simply misdirection on Toha’s part — intended to confuse and throw off investigators. Perhaps this even explains the Avdeev surname surfacing in the registration records from one of Toha’s domains.

But sometimes the simplest answer is the correct one. “Toha” is a common Slavic nickname for someone with the first name “Anton,” and that matches the name in the registration records for more than a dozen domains tied to Toha’s toschka2003@yandex.ru email address: Anton Medvedovskiy.

Constella Intelligence finds there is an Anton Gannadievich Medvedovskiy living in Kiev who will be 38 years old in December. This individual owns the email address itsmail@i.ua, as well an an Airbnb account featuring a profile photo of a man with roughly the same hairline as the suspect in the blurred photos released by the Ukrainian police. Mr. Medvedovskiy did not respond to a request for comment.

My take on the takedown is that the Ukrainian authorities likely arrested Medvedovskiy. Toha shared on DaMaGeLab in 2005 that he had recently finished the 11th grade and was studying at a university — a time when Mevedovskiy would have been around 18 years old. On Dec. 11, 2006, fellow Exploit members wished Toha a happy birthday. Records exposed in a 2022 hack at the Ukrainian public services portal diia.gov.ua show that Mr. Medvedovskiy’s birthday is Dec. 11, 1987.

The law enforcement action and resulting confusion about the identity of the detained has thrown the Russian cybercrime forum scene into disarray in recent weeks, with lengthy and heated arguments about XSS’s future spooling out across the forums.

XSS relaunched on a new Tor address shortly after the authorities plastered their seizure notice on the forum’s  homepage, but all of the trusted moderators from the old forum were dismissed without explanation. Existing members saw their forum account balances drop to zero, and were asked to plunk down a deposit to register at the new forum. The new XSS “admin” said they were in contact with the previous owners and that the changes were to help rebuild security and trust within the community.

However, the new admin’s assurances appear to have done little to assuage the worst fears of the forum’s erstwhile members, most of whom seem to be keeping their distance from the relaunched site for now.

Indeed, if there is one common understanding amid all of these discussions about the seizure of XSS, it is that Ukrainian and French authorities now have several years worth of private messages between XSS forum users, as well as contact rosters and other user data linked to the seized Jabber server.

“The myth of the ‘trusted person’ is shattered,” the user “GordonBellford” cautioned on Aug. 3 in an Exploit forum thread about the XSS admin arrest. “The forum is run by strangers. They got everything. Two years of Jabber server logs. Full backup and forum database.”

GordonBellford continued:

And the scariest thing is: this data array is not just an archive. It is material for analysis that has ALREADY BEEN DONE . With the help of modern tools, they see everything:

Graphs of your contacts and activity.
Relationships between nicknames, emails, password hashes and Jabber ID.
Timestamps, IP addresses and digital fingerprints.
Your unique writing style, phraseology, punctuation, consistency of grammatical errors, and even typical typos that will link your accounts on different platforms.

They are not looking for a needle in a haystack. They simply sifted the haystack through the AI sieve and got ready-made dossiers.

How Did Authorities Identify the Alleged Lockbit Boss?

Last week, the United States joined the U.K. and Australia in sanctioning and charging a Russian man named Dmitry Yuryevich Khoroshev as the leader of the infamous LockBit ransomware group. LockBit’s leader “LockBitSupp” claims the feds named the wrong guy, saying the charges don’t explain how they connected him to Khoroshev. This post examines the activities of Khoroshev’s many alter egos on the cybercrime forums, and tracks the career of a gifted malware author who has written and sold malicious code for the past 14 years.

On May 7, the U.S. Department of Justice indicted Khoroshev on 26 criminal counts, including extortion, wire fraud, and conspiracy. The government alleges Khoroshev created, sold and used the LockBit ransomware strain to personally extort more than $100 million from hundreds of victim organizations, and that LockBit as a group extorted roughly half a billion dollars over four years.

Federal investigators say Khoroshev ran LockBit as a “ransomware-as-a-service” operation, wherein he kept 20 percent of any ransom amount paid by a victim organization infected with his code, with the remaining 80 percent of the payment going to LockBit affiliates responsible for spreading the malware.

Financial sanctions levied against Khoroshev by the U.S. Department of the Treasury listed his known email and street address (in Voronezh, in southwest Russia), passport number, and even his tax ID number (hello, Russian tax authorities). The Treasury filing says Khoroshev used the emails sitedev5@yandex.ru, and khoroshev1@icloud.com.

According to DomainTools.com, the address sitedev5@yandex.ru was used to register at least six domains, including a Russian business registered in Khoroshev’s name called tkaner.com, which is a blog about clothing and fabrics.

A search at the breach-tracking service Constella Intelligence on the phone number in Tkaner’s registration records  — 7.9521020220 — brings up multiple official Russian government documents listing the number’s owner as Dmitri Yurievich Khoroshev.

Another domain registered to that phone number was stairwell[.]ru, which at one point advertised the sale of wooden staircases. Constella finds that the email addresses webmaster@stairwell.ru and admin@stairwell.ru used the password 225948.

DomainTools reports that stairwell.ru for several years included the registrant’s name as “Dmitrij Ju Horoshev,” and the email address pin@darktower.su. According to Constella, this email address was used in 2010 to register an account for a Dmitry Yurievich Khoroshev from Voronezh, Russia at the hosting provider firstvds.ru.

Cyber intelligence firm Intel 471 finds that pin@darktower.ru was used by a Russian-speaking member called Pin on the English-language cybercrime forum Opensc. Pin was active on Opensc around March 2012, and authored 13 posts that mostly concerned data encryption issues, or how to fix bugs in code.

Other posts concerned custom code Pin claimed to have written that would bypass memory protections on Windows XP and Windows 7 systems, and inject malware into memory space normally allocated to trusted applications on a Windows machine.

Pin also was active at that same time on the Russian-language security forum Antichat, where they told fellow forum members to contact them at the ICQ instant messenger number 669316.

NEROWOLFE

A search on the ICQ number 669316 at Intel 471 shows that in April 2011, a user by the name NeroWolfe joined the Russian cybercrime forum Zloy using the email address d.horoshev@gmail.com, and from an Internet address in Voronezh, RU.

Constella finds the same password tied to webmaster@stairwell.ru (225948) was used by the email address 3k@xakep.ru, which Intel 471 says was registered to more than a dozen NeroWolfe accounts across just as many Russian cybercrime forums between 2011 and 2015.

NeroWolfe’s introductory post to the forum Verified in Oct. 2011 said he was a system administrator and C++ coder.

“Installing SpyEYE, ZeuS, any DDoS and spam admin panels,” NeroWolfe wrote. This user said they specialize in developing malware, creating computer worms, and crafting new ways to hijack Web browsers.

“I can provide my portfolio on request,” NeroWolfe wrote. “P.S. I don’t modify someone else’s code or work with someone else’s frameworks.”

In April 2013, NeroWolfe wrote in a private message to another Verified forum user that he was selling a malware “loader” program that could bypass all of the security protections on Windows XP and Windows 7.

“The access to the network is slightly restricted,” NeroWolfe said of the loader, which he was selling for $5,000. “You won’t manage to bind a port. However, it’s quite possible to send data. The code is written in C.”

In an October 2013 discussion on the cybercrime forum Exploit, NeroWolfe weighed in on the karmic ramifications of ransomware. At the time, ransomware-as-a-service didn’t exist yet, and many members of Exploit were still making good money from “lockers,” relatively crude programs that locked the user out of their system until they agreed to make a small payment (usually a few hundred dollars via prepaid Green Dot cards).

Lockers, which presaged the coming ransomware scourge, were generally viewed by the Russian-speaking cybercrime forums as harmless moneymaking opportunities, because they usually didn’t seek to harm the host computer or endanger files on the system. Also, there were still plenty of locker programs that aspiring cybercriminals could either buy or rent to make a steady income.

NeroWolfe reminded forum denizens that they were just as vulnerable to ransomware attacks as their would-be victims, and that what goes around comes around.

“Guys, do you have a conscience?,” NeroWolfe wrote. “Okay, lockers, network gopstop aka business in Russian. The last thing was always squeezed out of the suckers. But encoders, no one is protected from them, including the local audience.”

If Khoroshev was ever worried that someone outside of Russia might be able to connect his early hacker handles to his real life persona, that’s not clear from reviewing his history online. In fact, the same email address tied to so many of NeroWolfe’s accounts on the forums — 3k@xakep.ru — was used in 2011 to create an account for a Dmitry Yurevich Khoroshev on the Russian social media network Vkontakte.

NeroWolfe seems to have abandoned all of his forum accounts sometime in 2016. In November 2016, an exploit[.]ru member filed an official complaint against NeroWolfe, saying NeroWolfe had been paid $2,000 to produce custom code but never finished the project and vanished.

It’s unclear what happened to NeroWolfe or to Khoroshev during this time. Maybe he got arrested, or some close associates did. Perhaps he just decided it was time to lay low and hit the reset on his operational security efforts, given his past failures in this regard. It’s also possible NeroWolfe landed a real job somewhere for a few years, fathered a child, and/or had to put his cybercrime career on hold.

PUTINKRAB

Or perhaps Khoroshev saw the coming ransomware industry for the endless pot of gold that it was about to become, and then dedicated himself to working on custom ransomware code. That’s what the government believes.

The indictment against Khoroshev says he used the hacker nickname Putinkrab, and Intel 471 says this corresponds to a username that was first registered across three major Russian cybercrime forums in early 2019.

KrebsOnSecurity could find no obvious connections between Putinkrab and any of Khoroshev’s older identities. However, if Putinkrab was Khoroshev, he would have learned from his past mistakes and started fresh with a new identity (which he did). But also, it is likely the government hasn’t shared all of the intelligence it has collected against him (more on that in a bit).

Putinkrab’s first posts on the Russian cybercrime forums XSS, Exploit and UFOLabs saw this user selling ransomware source code written in C.

In April 2019, Putkinkrab offered an affiliate program that would run on top of his custom-made ransomware code.

“I want to work for a share of the ransoms: 20/80,” Putinkrab wrote on Exploit. “20 percent is my percentage for the work, you get 80% of the ransoms. The percentage can be reduced up to 10/90 if the volumes are good. But now, temporarily, until the service is fully automated, we are working using a different algorithm.”

Throughout the summer of 2019, Putinkrab posted multiple updates to Exploit about new features being added to his ransomware strain, as well as novel evasion techniques to avoid detection by security tools. He also told forum members he was looking for investors for a new ransomware project based on his code.

In response to an Exploit member who complained that the security industry was making it harder to profit from ransomware, Putinkrab said that was because so many cybercriminals were relying on crappy ransomware code.

“The vast majority of top antiviruses have acquired behavioral analysis, which blocks 95% of crypto-lockers at their root,” Putinkrab wrote. “Cryptolockers made a lot of noise in the press, but lazy system administrators don’t make backups after that. The vast majority of cryptolockers are written by people who have little understanding of cryptography. Therefore, decryptors appear on the Internet, and with them the hope that files can be decrypted without paying a ransom. They just sit and wait. Contact with the owner of the key is lost over time.”

Putinkrab said he had every confidence his ransomware code was a game-changer, and a huge money machine.

“The game is just gaining momentum,” Putinkrab wrote. “Weak players lose and are eliminated.”

The rest of his response was structured like a poem:

“In this world, the strongest survive.
Our life is just a struggle.
The winner will be the smartest,
Who has his head on his shoulders.”

Putinkrab’s final post came on August 23, 2019. The Justice Department says the LockBit ransomware affiliate program was officially launched five months later. From there on out, the government says, Khoroshev adopted the persona of LockBitSupp. In his introductory post on Exploit, LockBit’s mastermind said the ransomware strain had been in development since September 2019.

The original LockBit malware was written in C (a language that NeroWolfe excelled at). Here’s the original description of LockBit, from its maker:

“The software is written in C and Assembler; encryption is performed through the I/O Completion Port; there is a port scanning local networks and an option to find all DFS, SMB, WebDAV network shares, an admin panel in Tor, automatic test decryption; a decryption tool is provided; there is a chat with Push notifications, a Jabber bot that forwards correspondence and an option to terminate services/processes in line which prevent the ransomware from opening files at a certain moment. The ransomware sets file permissions and removes blocking attributes, deletes shadow copies, clears logs and mounts hidden partitions; there is an option to drag-and-drop files/folders and a console/hidden mode. The ransomware encrypts files in parts in various places: the larger the file size, the more parts there are. The algorithms used are AES + RSA.

You are the one who determines the ransom amount after communicating with the victim. The ransom paid in any currency that suits you will be transferred to your wallets. The Jabber bot serves as an admin panel and is used for banning, providing decryption tools, chatting – Jabber is used for absolutely everything.”

CONCLUSION

Does the above timeline prove that NeroWolfe/Khoroshev is LockBitSupp? No. However, it does indicate Khoroshev was for many years deeply invested in countless schemes involving botnets, stolen data, and malware he wrote that others used to great effect. NeroWolfe’s many private messages from fellow forum members confirm this.

NeroWolfe’s specialty was creating custom code that employed novel stealth and evasion techniques, and he was always quick to volunteer his services on the forums whenever anyone was looking help on a malware project that called for a strong C or C++ programmer.

Someone with those qualifications — as well as demonstrated mastery of data encryption and decryption techniques — would have been in great demand by the ransomware-as-a-service industry that took off at around the same time NeroWolfe vanished from the forums.

Someone like that who is near or at the top of their game vis-a-vis their peers does not simply walk away from that level of influence, community status, and potential income stream unless forced to do so by circumstances beyond their immediate control.

It’s important to note that Putinkrab didn’t just materialize out of thin air in 2019 — suddenly endowed with knowledge about how to write advanced, stealthy ransomware strains. That knowledge clearly came from someone who’d already had years of experience building and deploying ransomware strains against real-life victim organizations.

Thus, whoever Putinkrab was before they adopted that moniker, it’s a safe bet they were involved in the development and use of earlier, highly successful ransomware strains. One strong possible candidate is Cerber ransomware, the most popular and effective affiliate program operating between early 2016 and mid-2017. Cerber thrived because it emerged as an early mover in the market for ransomware-as-a-service offerings.

In February 2024, the FBI seized LockBit’s cybercrime infrastructure on the dark web, following an apparently lengthy infiltration of the group’s operations. The United States has already indicted and sanctioned at least five other alleged LockBit ringleaders or affiliates, so presumably the feds have been able to draw additional resources from those investigations.

Also, it seems likely that the three national intelligence agencies involved in bringing these charges are not showing all of their cards. For example, the Treasury documents on Khoroshev mention a single cryptocurrency address, and yet experts interviewed for this story say there are no obvious clues connecting this address to Khoroshev or Putinkrab.

But given that LockBitSupp has been actively involved in Lockbit ransomware attacks against organizations for four years now, the government almost certainly has an extensive list of the LockBit leader’s various cryptocurrency addresses — and probably even his bank accounts in Russia. And no doubt the money trail from some of those transactions was traceable to its ultimate beneficiary (or close enough).

Not long after Khoroshev was charged as the leader of LockBit, a number of open-source intelligence accounts on Telegram began extending the information released by the Treasury Department. Within hours, these sleuths had unearthed more than a dozen credit card accounts used by Khoroshev over the past decade, as well as his various bank account numbers in Russia.

The point is, this post is based on data that’s available to and verifiable by KrebsOnSecurity. Woodward & Bernstein’s source in the Watergate investigation — Deep Throat — famously told the two reporters to “follow the money.” This is always excellent advice. But these days, that can be a lot easier said than done — especially with people who a) do not wish to be found, and b) don’t exactly file annual reports.