ESP32 Hash Monster Fills Pockets With Packets

Unless you’re reading this from the middle of the ocean or deep in the forest, it’s a pretty safe bet there’s WiFi packets zipping all around you right now. Capturing them is just a matter of having the right hardware and software, and from there, you can get to work on cracking the key used to encrypt them. While such things can obviously have nefarious connotations, there are certainly legitimate reasons for auditing the strength of the wireless networks in the area.

It might not have the computational horsepower to crack any encryption itself, but the ESP32 M5Stack is more than up to the task of capturing WiFi packets if you install the Hash Monster firmware developed by [G4lile0]. Even if you don’t intend on taking things farther, this project makes finding WiFi access points and grabbing their packets a fascinating diversion with the addition of a few graphs and an animated character (the eponymous monster itself) that feeds on all those invisible 1s and 0s in the air.

There’s some excellent documentation floating around that shows you the start to finish process of popping open a WiFi network with the help of Hash Monster, but that’s only the beginning of what’s possible with this gadget. A quick search uncovers a number of software projects that make use of the specific advantages of the M5Stack compared to more traditional ESP32 boards, namely the built-in screen, buttons, and battery. We’ve even seen it used in a few builds here on Hackaday, such as this DIY thermal camera and custom shipboard computer system.

[Thanks to Manuel for the tip.]

This Week In Security: Bluetooth Hacking, NEC Phones, And Malicious Tor Nodes

One of the fun things about vulnerability research is that there are so many places for bugs to hide. Modern devices have multiple processors, bits of radio hardware, and millions of lines of code. When [Veronica Kovah] of Dark Mentor LLC decided to start vulnerability research on the Bluetooth Low Energy protocol, she opted to target the link layer itself, rather than the code stack running as part of the main OS. What’s interesting is that the link layer has to process data before any authentication is performed, so if a vulnerability is found here, it’s guaranteed to be pre-authentication. Also of interest, many different devices are likely to share the same BLE chipset, meaning these vulnerabilities will show up on many different devices. [Veronica] shares some great info on how to get started, as well as the details on the vulnerabilities she found, in the PDF whitepaper. (Just a quick note, this link isn’t to the raw PDF, but pulls up a GitHub PDF viewer.) There is also a video presentation of the findings, if that’s more your speed.

The first vuln we’ll look at is CVE-2019-15948, which affects a handful of Texas Instruments BT/BLE chips. The problem is in how BLE advertisement packets are handled. An advertisement packet should always contain a data length of at least six bytes, which is reserved for the sending device address. Part of the packet parsing process is to subtract six from the packet length and do a memcpy using that value as the length. A malicious packet can have a length of less than six, and the result is that the copy length integer underflows, becoming a large value, and overwriting the current stack. To actually turn this into an exploit, a pair of data packets are sent repeatedly, to put malicious code in the place where program execution will jump to.

The second vulnerability of note, CVE-2020-15531 targets a Silicon Labs BLE chip, and uses malformed extended advertisement packets to trigger a buffer overflow. Specifically, the sent message is longer than the specification says it should be. Rather than drop this malformed message, the chip’s firmware processes it, which triggers a buffer overflow. Going a step further, this chip has non-volatile firmware, and it’s possible to modify that firmware permanently. [Veronica] points out that even embedded chips like these should have some sort of secure boot implementation, to prevent these sort of persistent attacks.
Continue reading “This Week In Security: Bluetooth Hacking, NEC Phones, And Malicious Tor Nodes”

Physical Security Hack Chat With Deviant Ollam

Join us on Wednesday, June 3 at noon Pacific for the Physical Security Hack Chat with Deviant Ollam!

You can throw as many resources as possible into securing your systems — patch every vulnerability religiously, train all your users, monitor their traffic, eliminate every conceivable side-channel attack, or even totally air-gap your system — but it all amounts to exactly zero if somebody leaves a door propped open. Or if you’ve put a $5 padlock on a critical gate. Or if your RFID access control system is easily hacked. Ignore details like that and you’re just inviting trouble in.

Once the black-hats are on the inside, their job becomes orders of magnitude easier. Nothing beats hands-on access to a system when it comes to compromising it, and even if the attacker isn’t directly interfacing with your system, having him or her on the inside makes social engineering attacks that much simpler. System security starts with physical security, and physical security starts with understanding how to keep the doors locked.

join-hack-chatTo help us dig into that, Deviant Ollam will stop by the Hack Chat. Deviant works as a physical security consultant and he’s a fixture on the security con circuit and denizen of many lockpicking villages. He’s well-versed in what it takes to keep hardware safe from unauthorized visits or to keep it from disappearing entirely. From CCTV systems to elevator hacks to just about every possible way to defeat a locked door, Deviant has quite a bag of physical security tricks, and he’ll share his insights on keeping stuff safe in a dangerous world.

Our Hack Chats are live community events in the Hack Chat group messaging. This week we’ll be sitting down on Wednesday, June 3 at 12:00 PM Pacific time. If time zones have you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

Pentesting Hack Chat This Wednesday

Join us on Wednesday, May 13 at noon Pacific for the Pentesting Hack Chat with Eric Escobar!

Ask anyone in this community to name their dream jobs and chances are pretty good that penetration tester will be somewhere on the shortlist. Pentesters are allowed — nay, encouraged — to break into secure systems, to test the limits and find weak points that malicious hackers can use to gain access. The challenge of hacking and the thrill of potentially getting caught combined with no chance of prosecution? And you get paid for it? Sounds good to us!

Professional pentesting is not all cops-and-robbers fun, of course. Pentesters have to stay abreast of the latest vulnerabilities and know what weaknesses are likely to exist at a given facility so they know what to target. There are endless hours of research, often laborious social engineering, and weeks of preparation before actually attempting to penetrate a client site. The attack could be as complex as deploying wireless pentesting assets via FedEx, or as simple as sprinkling thumb drives in the parking lot. But when it comes, a pentest often reveals just how little return companies are getting on their security investment.

As a consultant for a security firm, Eric Escobar gets to challenge companies on a daily basis. He’s also a regular on the con circuit, participating in challenges like Wireless CTF at DEF CON… until he won too many times. Now he helps design and execute the challenges, helping to share his knowledge with other aspiring pentesters. And he’ll stop by the Hack Chat to do the same with us, and tell us all about the business of keeping other businesses in business.

join-hack-chatOur Hack Chats are live community events in the Hack Chat group messaging. This week we’ll be sitting down on Wednesday, May 13 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about. Continue reading “Pentesting Hack Chat This Wednesday”

An Open Hardware Rubber Ducky

No it’s not an open source version of Bert’s favorite bathtime toy (though seriously, let us know if you see one), the PocketAdmin by [Radik Bechmetov] is intended to be an alternative to the well-known “USB Rubber Ducky” penetration testing tool from Hak5. It might look like a standard USB flash drive, but underneath that black plastic enclosure is a whole lot of digital mischief waiting to spill out.

The general idea is that the PocketAdmin appears to the host computer as either a USB Human Interface Device (keyboard, mouse, etc) or a USB Mass Storage Device. In either event, the user has the ability to craft custom payloads which can exploit the operating system’s inherent trust in locally connected devices. The most common example is mimicking a USB keyboard that starts “typing” once connected to the computer.

You can even configure what vendor and product IDs the PocketAdmin advertises, allowing you to more accurately spoof various devices. [Radik] has included some other interesting features, such as the ability to launch different payloads depending on the detected operating system. That way it won’t waste time trying to bang out Windows commands when it’s connected to a Linux box.

The hardware is designed to be as easy and cheap to replicate as possible. The heavy lifting is done by a STM32F072C8T6 microcontroller, coupled with a W25Q256FVFG 32MiB flash chip to store the payloads. Beyond that, the BOM consists mainly of passives and a few obvious bits like the male USB connector. [Radik] has even provided a link to where you can buy the convincing looking USB “flash drive” enclosure.

We’ve seen low-cost DIY versions of the USB Rubber Ducky in the past, but PocketAdmin is interesting in that it seems like [Radik] is looking to break new ground with this project rather than just copy what’s already been done. This will definitely be one to watch as the 2019 Hackaday Prize heats up.

“Watch Dogs” Inspired Hacking Drone Takes Flight

They say that life imitates art, which in modern parlance basically means if you see something cool in a video game, movie or TV show, you might be inclined to try and build your own version. Naturally, such things generally come in the form of simple props, perhaps with the occasional embedded LED or noise making circuit. It’s not as if you can really build a phaser from Star Trek or a phone booth that’s bigger on the inside.

But after seeing the hacking quadcopter featured in the video game Watch Dogs 2, [Glytch] was inspired to start work on a real-world version. It doesn’t look much like the drone from the game, but that was never the point. The idea was to see how practical a small flying penetration testing platform is with current technology, and judging by the final build, we’d say he got his answer.

All the flight electronics are off the shelf quadcopter gear. It’s running on a Betaflight OMNIBUS F4 Pro V2 Flight controller with an M8N GPS mounted in the front and controlling the 2006 2400KV motors with a DYS F20A ESC. Interestingly [Glytch] is experimenting with using LG HG2 lithium-ion cells to power the quad rather than the more traditional lithium-polymer pack, though he does mention there are some issues with the voltage curve between the two battery technologies.

But the real star of the show is the payload: a Hak5 Pineapple Nano. As the Pineapple provides a turn-key penetration testing platform on its own, [Glytch] just needed a way to safely carry it and keep it powered. The custom frame keeps it snug, and the 5 Volt Battery Eliminator Circuit (BEC) on the DYS F20A ESC combined with a female USB port allows powering the Pineapple without having to make any hardware modifications.

We’ve seen quadcopters with digital weaponry before, though not nearly as many as you might think. But as even the toy grade quadcopters become increasingly capable, we imagine the airborne hacking revolution isn’t far away.

Continue reading ““Watch Dogs” Inspired Hacking Drone Takes Flight”

Seek And Exploit Security Vulnerabilities In An Infusion Pump

Infusion pumps and other medical devices are not your typical everyday, off-the-shelf embedded system. Best case scenario, you will rarely, if ever, come across one in your life. So for wide-spread exploitation, chances are that they simply seem too exotic for anyone to bother exploring their weaknesses. Yet their impact on a person’s well-being makes potential security holes tremendously more severe in case someone decides to bother one day after all.

[Scott Gayou] is one of those someones, and he didn’t shy away from spending hundreds of hours of his free time inspecting the Smiths Medical Medfusion 4000 infusion pump for any possible security vulnerabilities. Looking at different angles for his threat model, he started with the physical handling of the device’s user interface. This allowed him to enable the external communication protocols settings, which in turn opened to the device’s FTP and Telnet ports. Not to give too much away, but he manages to gain access to both the file system content and — as a result of that — to the system’s login credentials. This alone can be clearly considered a success, but for [Scott], it merely opened a door that eventually resulted in desoldering the memory chips to reverse engineer the bootloader and firmware, and ultimately executing his own code on the device.

Understanding the implications of his discoveries, [Scott] waited long enough to publish his research so the manufacturer could address and handle these security issues. So kudos to him for fighting the good fight. And just in case the thought of someone gaining control over a machine that is crucial to your vitality doesn’t scare you enough yet, go ahead and imagine that device was actually implanted in your body.