Katie: OK, let's dive in. So picture this. You've got this high stakes digital game of cat and mouse, right, happening deep inside a network. You've got a red team, the attackers, they're inside and they're looking for, well, the ultimate prize, total control.
James: And on the other side, the blue team, the defenders, scrambling, trying to spot them, trying to shut it all down. It's intense.
Katie: Exactly. And that's the scene the source material we're looking at today just drops us right into.
James: Yeah. And this material, it's really quite fascinating. It's episode four of something called the Purple Team Chronicles. And it focuses on this specific incident they label the golden ticket coup.
Katie: A golden ticket coup sounds dramatic. It kind of reads like a cybersecurity incident report, but, you know, from the trenches.
James: It does. Very detailed.
Katie: So our mission for this deep dive is to really unpack this chronicle. We want to understand this pretty sophisticated attack technique they used, one that gives attackers just immense power.
James: Right. How did they actually pull it off in this specific scenario?
Katie: And maybe even more importantly, how did the defenders, Michelle's team, figure it out and stop it? And we're sticking only to the details given right here in this source.
James: Think of it as zooming in on one critical moment, you know, the battle for domain control, how attackers go for those master keys and how defenders can potentially spot them and crucially invalidate them.
Katie: OK, so let's start with the attack. According to this chronicle, the red team led by this person, Alex, they'd sort of hit a wall.
James: Yep. Shell's blue team had done a good job. They'd blocked off a lot of the attackers usual methods for moving sideways laterally through the network.
Katie: Right. The source actually quotes Alex thinking this next move is the final card to play. They're running out of options.
James: And that's pretty typical, right? When the standard paths are blocked, skilled attackers often pivot. They aim higher.
Katie: Aim higher meaning?
James: Meaning they target the foundation. In a Windows domain environment, the ultimate goal, the real keys to the kingdom, is getting domain level compromise. Often through messing with Kerberos authentication.
Katie: Which brings us right to the technique they used here. The Chronicle says they leveraged access they already had, crucially, on a compromised domain controller and used something called DC-Sync functionality, which, it explains, lets them extract the KRBTG hash.
James: Ah, the KRBTG hash. Okay, that's the big one. It's fundamental. This isn't just any old password hash.
Katie: Why is it so special?
James: It belongs to, well, a very special account used only by the key distribution center service on a domain controller. This account's job is basically to encrypt and sign every single Kerberos ticket in the whole domain.
Katie: Every single one.
James: Every one. It's the absolute bedrock of trust for Kerberos. So if you get that hash, you can essentially start minting your own trust, creating tickets that look completely legitimate.
Katie: Wow. Okay. And the source is super specific here. It gives the tactic ID for getting the hash. T1003-006-OS-credential-dumping using DC Sync. And it even tells us the tool and the command. Mimikatz.exe firstprivilege.debug then lcdump.lsa inject
James: Yeah, that Mimikatz command, it's clever. It basically tricks the domain controller. Makes it think the attacker's machine is just another DC asking for replication data. Standard stuff.
Katie: But it's not standard.
James: No, it's specifically targeting that KeraBTG account info. Getting that hash, it's like stealing the master template. The template for the stamp that approves all the other keys.
Katie: Okay, master template stolen. They've got the KarabeeTGE hash. What's next? The Chronicle says they use it to forge the golden ticket.
James: Exactly. And it's called golden for a reason. Having that legitimate KarabeeTGE hash means you can now create a Kerberos ticket, granting ticket, a TGT for pretty much any user you want in that domain. Real or even fake.
Katie: A user. Seriously.
James: Yep. And you can set how long it's valid for. You could stuff it with powerful group memberships like, say, domain admins. And it bypasses all the usual checks. Because when the key distribution center sees this forged ticket, it checks the signature. And the signature was made with the real stolen care BTT ad hash. So as far as the KDC is concerned, perfectly valid. Authenticity confirmed.
Katie: The source, again, gives us the nitty-gritty. Tactic ID T1558.001, steal or forge Kerberos tickets. And the exact Mimikatz command at kerberos.golden.
James: With all the parameters.
Katie: Right. Specifying the user as administrator, the domain, vrxdomain.local, the SID, the actual stolen Kerebi TGD hash, and this ID 500. What's ID 500?
James: That's the default relative ID, the RID for the built-in administrator account in a Windows domain.
Katie: Yeah.
James: So they're specifically targeting maximum privilege.
Katie: OK, so that command creates the fake ticket file, then what? They have to use it, right?
James: Correct. The next step, also mentioned in the source, is loading that forged ticket into the attacker's current session. They use Mimicats.exe again, this time with Kerberos.ptt, ticket.kerby.
Katie: PTT.
James: Pass the ticket. That's exactly what it sounds like. Takes the ticket from the file and injects it into memory, ready to be used for authentication.
Katie: And the result, I mean, the source quotes Alex's thoughts here and it's pretty chilling. Unrestricted access across the domain.
James: Impersonating any user, accessing any resource, remaining undetected.
Katie: They call it a master key and the thought, this is what it means to own the domain. That really hits home the power they feel they have.
James: It absolutely does because now they can move anywhere, do anything as the highest authority without needing to crack any more passwords or compromise individual accounts. And the scary part... Oh, what's that? From the perspective of traditional security monitoring things, looking for failed logins, password guessing, this often was completely normal. Just valid Kerberos traffic.
Katie: Okay, so Red Team thinks they've won. Master key acquired. Let's flip the script. How did the blue team, Michelle's team, possibly find this? This is where it gets really interesting on the defense side, according to the Chronicle.
James: Right. So what the source tells us is Michelle was actually doing a post-incident review. They'd already stopped some earlier stuff, the lateral movement attempts.
Katie: OK.
James: And while digging through the activity logs after that, she spots something odd, an unexpected spike in Kerberos authentication requests targeting critical servers.
Katie: And her gut reaction, quoted in the source, is perfect. Nothing should have triggered that. That instinct noticing the anomaly. That's crucial.
James: Absolutely. So the source says she immediately starts digging into the security locks. It even shows the command she uses. Get wine event, log name security, where object ID in 4769-47701.
Katie: Okay, event IDs 4769 and 4771. Why those?
James: Super important for Cabaro's monitoring. 4769 is Cabaro's service ticket was requested. Basically, someone successfully got a ticket to access a specific service. 4771 is Cabaro's pre-authentication failed? Less relevant here, but good to check. She's looking at those successful 47769 events.
Katie: And she sees lots of them. That's the spike.
James: Yes. But it's what she finds when she looks closer that matters. The source highlights this as the critical finding.
Katie: What was it?
James: The tickets themselves. They look perfectly valid. They pass the checks. And this is the key. They were originating from a host computer that had absolutely no legitimate reason to be issuing Cabrera service tickets like that.
Katie: So not the ticket itself being bad, but where it came from.
James: Exactly. That's the core detection insight described here. The tickets validated because remember, they were signed with the real stolen KRBTGT hash, but the context was all wrong. These requests weren't coming from a domain controller. The source actually uses the phrase, it smelled like a golden clicket attack. It's not about an invalid ticket. It's about a valid ticket coming from a malicious source.
Katie: Okay, she smells the golden ticket. What's the immediate response described in the Chronicle? What do they do first?
James: The number one most critical step, according to the source, rotate the CAREBTGT password immediately.
Katie: Just reset it.
James: Yes. But crucially, and the Chronicle really stresses this, it has to be done twice.
Katie: Twice? Why twice? That seems specific.
James: It's super important. The source explains it well. The first reset changes the underlying CAREBTG key. That immediately invalidates any golden tickets out there that were forged using the old skull and hash. They just won't work anymore.
Katie: OK, that makes sense. So why the second reset?
James: The second reset, done usually after a short delay matching your Kerberos policy, invalidates the previous KRBTGD key history that Windows keeps. It ensures there's absolutely no way for older keys or tickets derived from that first new hash to still be valid. It's about thorough cleanup and ensuring full invalidation across generations.
Katie: Right. Closing any potential loopholes from the rotation process itself makes sense.
James: It's vital. And Michelle's quoted reaction nails it. No skeleton keys in my house were resetting the locks. Double locking, essentially.
Katie: Love that. OK, so resetting the KRBTGD password twice is paramount. What else did the blue team do? The source lists a few parallel actions.
James: Yeah, it outlines a clear sequence. First, they detected that anomalous Kerberos activity spike. Then, they used this technology mentioned, Vicarious VRX, to cross-reference logs and pinpoint the specific host that was issuing these unauthorized tickets.
Katie: Okay, identify the source.
James: Then, perform that critical DoubleCare BTG password reset. After that, block all network traffic coming from that attacker's compromised host. Isolated.
Katie: Containment.
James: Exactly. And finally, kick off a forensic capture of that machine to figure out everything it did and how it got compromised in the first place.
Katie: That sounds like a solid step-by-step response playbook. Detection, investigation, mitigation, isolation, evidence.
James: Definitely. A well-orchestrated response.
Katie: Let's talk a bit more about that tech mentioned, Vicarious VRX. How does the source say it helped Michelle's team here?
James: So the Chronicle highlights its role in connecting the dots. It didn't just see the spike in Kerberos logs, event ID 4769. It correlated that spike with other recent alerts where suspicious activities flag on specific hosts in the network.
Katie: So it helped provide context, like, hey, these weird Kerberos events are coming from the same machine where we saw X, Y, and Z happen earlier.
James: Precisely. And crucially, the sources, the technology flagged the behavior, the unauthorized ticket issuing, even though the tickets themselves technically looked OK because they had the valid signature. It understood the context was wrong.
Katie: That seems pretty advanced, looking beyond just signature validation.
James: Yeah, behavioral analysis. And importantly, the source mentioned VRX could launch a response playbook. This suggests automation.
Katie: Meaning?
James: Meaning, triggering those key actions, forcing the CaribB TG reset. Isolating the attacker's host wasn't necessarily someone manually typing commands under pressure. It could be initiated quickly through the system.
Katie: Ah, orchestration. The Chronicle emphasizes that this capability, orchestration at scale, is a major strength. It lets you execute these response strategies really fast, like in minutes instead of hours.
James: And in the golden ticket scenario, that speed is everything. Every minute the attacker has that ticket is another minute they can dig deeper, deploy ransomware, steal data, whatever. Closing that window fast is critical.
Katie: OK, let's connect this incident, this chronicle, back to the real world for a moment. The source makes a really important point about why this golden ticket technique is, well, so dangerous and why traditional security often misses it.
James: It boils down to that core problem we discussed. The credentials being used, the tickets, they look valid. They have the right signature.
Katie: Right. Not like a brute force attack setting off alarms.
James: Exactly. And this isn't some theoretical attack. The source explicitly mentions that techniques like this, or very similar ones involving Kerberos manipulation, have been used in major real-world cyberattacks. It cites things like NotPetya and operations by groups like APT29.
Katie: And in those real incidents, the impact cited was huge, partly because attackers could operate inside networks for weeks undetected.
James: Weeks, sometimes longer. All because they had these seemingly legitimate golden credentials that let them move around freely without raising red flags on basic security tools.
Katie: It really highlights that need for deeper visibility, doesn't it? You can't just look for the obvious failed login attempts.
James: Now, you have to understand normal authentication behavior, establish baselines, and then look for deviations, even if the credentials themselves seem OK. Look at the context, the source, the timing, the volume.
Katie: So let's try and wrap up the key takeaways from this specific chronicle, this golden ticket coup story. The source itself lists a few clear ones. First, golden tickets are called the ultimate stealth privilege escalation.
James: And because they're stealthy, detection demands more than just signatures. It requires, as we said, deep visibility into authentication behavior. Who's asking for tickets? For whom? From where? Is that normal?
Katie: Then there's the critical mitigation, rotating the VTGD password, and the absolute necessity, emphasized again, of doing it twice after you suspect a compromise.
James: Can't stress that enough. The double tap is crucial.
Katie: And finally, the source points to the role of technology, like the vicarious VRX mentioned here, providing that needed visibility, yes, but also the automation and orchestration to respond fast, turning a potentially hours-long manual process into something that can be replicated in minutes.
James: That rapid orchestrated response capability can be the difference between a contained incident and a full-blown disaster.
Katie: OK. So we've really walked through this specific scenario from the Purple Team Chronicles. We saw the red team forge their master key feeling like they own the domain.
James: That moment of perceived victory for Alex.
Katie: Right up until the blue team lead, Michelle, picks up on those subtle signals that anomalous Kerberos traffic smells the golden ticket.
James: and orchestrates that swift, decisive response. Resetting the locks, isolating the threat, regaining control. It's quite a narrative.
Katie: It really is. And the core lesson seems crystal clear. You absolutely need to understand how these sophisticated attacks like golden tickets work. But knowing isn't enough.
James: Right. The real defense comes from having that deep visibility into the right kind of network activity, especially authentication behavior. and crucially having the ability to act decisively and rapidly with an orchestrated response when you spot something wrong.
Katie: Now, the source material does give us a little teaser for what's next in these chronicles. The next installment is apparently titled From Adversaries to Allies, the Birth of a Purple Team.
James: Oh, interesting. From conflict to collaboration.
Katie: Exactly. So thinking about the intense conflict we just unpacked between Alex's red team and Michelle's blue team. What does that shift look like? How do you go from being adversaries trying to outwit each other to becoming allies, working together to build better defenses?
James: That's a fascinating question. How does shifting that fundamental mindset from pure opposition to collaboration change the whole picture for how we approach cybersecurity strategy, testing, and improvement?
Katie: Yeah, something to definitely chew on. How does that collaborative model work in practice? That's a good place to leave it for now.
