SEC536: Adversarial AI - Penetration Testing AI Systems


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Breaking Down September 2026's Discussion: Inside the Cybercrime Infrastructure Supply Chain
This month's SANS Threat Analysis Rundown went beneath the intrusions, the ransomware crews, and the malware families to the layer they all depend on: infrastructure. Bulletproof hosting, residential proxy networks, and AI-native attack tooling operate as a supply chain that threat actors rent instead of build, and that supply chain has absorbed a remarkable amount of enforcement pressure. In the past year, OFAC and its UK and Australian counterparts sanctioned Media Land and the front companies behind Aeza Group (November 2025), Google and partners disrupted the IPIDEA residential proxy network (January 2026), and the FBI, Google, and Lumen went after NetNut (July 2026). Every one of those actions mattered. None of them removed the capability.
To trace how that supply chain works and why it keeps surviving, I was joined by Will Thomas (@BushidoToken), Senior Threat Intelligence Advisor at Team Cymru, co-founder of the Curated Intelligence trust group, and my co-author on FOR589: Cybercrime Investigations, where he built the Cybercrime Underground day and the course's deep dive into infrastructure. Will is also a former colleague, so this was a conversation between two people who have spent years chasing this infrastructure side by side.
STAR stays practitioner-first: no vendor pitches and no recycled headlines, just a working-level conversation about what is happening and what defenders can do about it. Will works at a company with network visibility most of us will never have, so throughout the hour I kept pulling the conversation back to the version of the method you can run without a commercial NetFlow contract. You can catch the full replay of this episode on the SANS DFIR YouTube channel.
One note before the recap. We opened the stream with a look at the SANS DFIR Summit & Training 2026 in Arlington, Virginia (Summit October 15 to 16, training October 17 to 22). Heather Barnhart and Jason Higley are delivering back-to-back keynotes on the digital evidence behind two high-profile investigations, then returning to the stage together to compare what that evidence actually proved in each case. That portion is in-person only and will not show up in a recording, which is a good reason to be in the room.
I started with the plain question: what does a bulletproof hosting (BPH) provider sell that a normal VPS provider does not? Will's answer is that BPH is the foundational layer of the cybercriminal ecosystem. It is what lets operations last longer and resist the standard takedown attempts that companies and law enforcement rely on.
Law enforcement can and does take offensive action against these providers. The point is that the traditional, paperwork-driven takedown path does not work here, and that is exactly what customers of bulletproof hosting are paying for.
The Treasury designation from November 2025 is the cleanest public case study of how this layer behaves under pressure. OFAC, alongside Australia and the United Kingdom, sanctioned Media Land, a Russia-based BPH provider, along with members of its leadership and several sister companies. In the same action, OFAC and the UK designated Hypercore Ltd., which Treasury describes as a front company for Aeza Group, a BPH provider that had already been sanctioned in July 2025.
That second half is the lesson. Aeza was designated, and then it rebranded, stood up new infrastructure through a front company, and kept operating until the front company was designated too. We see the same move on the ransomware side, where sanctioned crews rebrand to put distance between themselves and the designated entity. Sanctions raise the cost of doing business. They do not end the business.
Media Land is the long-running example. Will described it as one of the longest-running BPH services there is, run for years as a business by an individual known by the handle Yalishanda. Intel 471 has tracked that actor for the better part of a decade, and the Yalishanda case study is one of the labs we teach in FOR589. Will's point was that without this class of provider, operations like LockBit and BlackSuit could not stage and exfiltrate stolen data to their own servers without losing those servers. Both names line up with the ransomware operations officials cited when the sanctions were announced.
Two days before the stream, Will published From the Disk to the Flows: Ransomware Infrastructure Analysis, and we walked through it on screen. Over roughly a year, Team Cymru worked with a DFIR partner across more than twenty ransomware investigations, covering Akira, DragonForce, Clop, MedusaLocker, Qilin, INC Ransom, and Lynx, in cases where network IOCs were actually recoverable. As anyone who has worked a ransomware incident knows, that is not a given. Everything gets encrypted, firewalls get turned off, and you are left assembling a puzzle out of scraps.
The part I wanted the audience to notice is what the post does not contain: IOCs. Because the indicators came from a partner's live engagements, they were not published. What Will shared instead is a set of queries that describe behavior, and that is the more useful artifact anyway. A few of the ideas translate directly to tooling you already have:
Where do you start without a commercial platform? Will's answer was Shodan and urlscan.io, which is how he got started tracking ransomware infrastructure, building fingerprints, and finding C2 panels, many of which still have static tells in an HTTP title or a certificate. We teach both in the course. One caution he raised about a popular alternative, FOFA: Know who develops the tools you query, and think about who can see those queries.
This is the question the STAR audience always asks, so we gave it room: If the guidance is to pay attention to the network an IP belongs to, should you just block bad ASNs?
Here is Will's answer:
The takeaway is to treat network-level blocks like any other indicator with a shelf life. Tie them to current behavior, review them, and age them out.
Residential proxy networks solve the same problem for an attacker as bulletproof hosting, which is hiding where traffic really comes from, but they are built in a completely different way. A bulletproof host is an actual hosting service. A residential proxy network is closer to a botnet assembled through the app economy.
Will walked through the model using IPIDEA and NetNut (also tracked as Popa), the two networks Google has gone after this year:
Remediation is close to impossible from the outside. You cannot submit a takedown request for a television, and you cannot seize millions of consumer devices. Will's view is that Google is one of the only organizations positioned to act, because it owns Android and the Play Store. That is what the IPIDEA and NetNut actions did: identify the SDKs, take down control domains, and use Play Protect to warn users and disable the offending apps. The scale of the cleanup problem is the catch. It can mean tens of thousands of legitimate apps with hundreds of millions of users.
Google itself described the results as degrading these networks, reducing the available device pool by millions, not eliminating them. I called it whack-a-mole on the stream and Will agreed. For a threat that can rotate through something like a million IPs a day, static IOC blocking is simply the wrong tool.
We looked at the difficulty from both sides.
For law enforcement, the old playbook was to find the criminal server, seize and preserve it, watch who connects to it, and work back to an arrest. With CDNs and residential proxies in the path, investigators now have to serve legal process on a provider, and there may be a thousand users behind that one IP at the same moment. Miss a single detail, such as the client port or a timestamp accurate to the second, and the trail ends. Will compared it to tracing cryptocurrency through mixers layered on mixers. It is the same obfuscation and layering, applied to network traffic.
For defenders, Will pointed to three log sources where this matters most: SSO sign-ins, Microsoft Entra ID sign-ins, and the login logs for your SaaS applications. We have watched plenty of SaaS compromises that came down to infostealer credentials and a successful login. If you are not recording who logs into what, with context on whether the source IP is a VPN or a proxy, criminals could be logging in every day without your knowledge.
The maturity path he described is practical:
I framed it this way on the stream: Most threat intel feeds are tuned to malware and intrusion activity. There is a whole layer underneath—the infrastructure supporting the campaign—that those feeds do not describe. Not getting hits is not the same as not having the activity. Will added the mistake he sees most often, which is organizations assuming they are covered because EDR is blocking the malware. The share of attacks that use malware at all is far lower than it used to be. As we said in our first episode, it is all about identity.
Should you hard-block logins from residential proxies? I asked directly whether an automatic lockout rule is too extreme. Will's personal view: Automate the lockout when the proxy tag is combined with other behavioral anomalies, such as an unusual time of day or a geography that account never uses. Otherwise, keep it as a critical alert that a SOC analyst verifies before locking the account. Do not act on the atomic indicator alone. Look at the behavior around it.
That is also the answer to the executive who wants to geo-block all of Eastern Europe. Geo-blocking has narrow uses, but as Will put it, most threat actors are proxying every single connection anyway, through a residential proxy, a VPS, or something else. The work of enrichment and filtering cannot be skipped.
A categorization note first, because Will is careful about it and so am I: Operational relay box (ORB) networks are primarily a China-nexus espionage phenomenon, not cybercrime. They belong in this episode because they do the same job as a residential proxy network, laundering the origin of a connection, just built by a different kind of operator with a different skill set.
Will's Project ORBITAL exists because he saw a gap: Plenty of CTI researchers know the term, but few grasp the scale. So he did what he has done before and built an open knowledge base, available on GitHub, assembled entirely from open source intelligence so that every claim can be verified. It catalogs which ORB networks exist, which adversaries have been reported using them, what devices they are built from, and what exploits are used to build them. Every entry cites its source, including research from Sekoia, Microsoft, Cisco Talos, SecurityScorecard, GreyNoise, Lumen, and Team Cymru. As I said on the stream, the project is a testament to what the community produces when people publish their work.
The honest limits are worth stating. Banners and certificates can tell you a device is probably part of a network. They cannot tell you whether an APT is actively routing through it right now. That takes flow visibility, which is a genuine commercial advantage. Historical lookups will also require some kind of service, whether that is Shodan or a platform like Team Cymru's. But the fingerprinting itself is work any team can start on today.
I asked Will how AI is disrupting this space, and his answer was stronger than I expected. In all the years Team Cymru has tracked criminal and nation-state infrastructure, he called this one of the largest trend changes they have seen: a meaningful share of the C2 servers they track suddenly running AI-related software, including agents, LLM front ends, and automated penetration testing tools. The tools are free, they are easy to use, and criminals will happily run them on stolen API keys.
The discovery story behind Tracking CyberStrikeAI Usage is a good lesson in pivoting. Amazon's threat intelligence team published research on an AI-augmented actor compromising FortiGate devices at scale and shared a handful of IP addresses. Will looked at the open ports on one of them and found a banner reading CyberStrikeAI, which the Amazon post had not mentioned. He built a fingerprint from that banner and went looking.
Will also pointed to the Team Cymru Threat Research account on X, which posts short intel drops. One recent thread used flow data to identify routing and proxy services that relay traffic between users in China and frontier AI models, the network-side view of activity Anthropic has described in its reporting on illicit distillation, where requests were relayed to Claude through networks of fraudulent accounts. As Will put it, AI tokens are becoming a currency, and there is now infrastructure built to farm them.
For defenders, the implication is volume. The barrier to running a competent, multi-stage attack chain against exposed edge devices just dropped, and what arrives at your perimeter will scale accordingly.
We closed by bringing it back to the spine of the episode. Takedowns matter. They are also hard, and the evidence of the past year is that they rarely remove a capability outright. Defending against this layer is hard too, especially when the traffic comes from someone's living room. That is not a reason to skip the work. It is the work.
If you take one thing from each pillar:
Infrastructure is the one thing an attack cannot skip. Every operation has to cross it somewhere, and that makes tracking it one of the most durable investments a defender can make.
These were not called out by name during the livestream, but they sit directly behind the research we discussed and are worth your time if you want to go a level deeper:
If you want to keep building on what we covered this month:
Next month on STAR, we will be back with another guest and another working-level conversation on what is actually moving in the threat landscape. Catch the replay of this episode and register for upcoming livestreams at the SANS Threat Analysis Rundown page.
Thanks to everyone who joined live or is catching the replay, and a special thanks to Will Thomas for showing his work. Publishing the queries, the fingerprints, and the sources so that other defenders can reproduce them is what makes this community better. See you next time.


Sean O’Connor is a cybersecurity professional with over 15 years of experience in intelligence, digital forensics, and threat analysis across both the private and public sectors.
Read more about Sean O'Connor