TurtleAuth DIY Security Token Gets (Re)designed For Durable, Everyday Use

May 21, 2022 by Donald Papp 15 Comments

[Samuel]’s first foray into making DIY hardware authentication tokens was a great success, but he soon realized that a device intended for everyday carry and use has a few different problems to solve, compared to a PCB that lives and works on a workbench. This led to TurtleAuth 2.1, redesigned for everyday use and lucky for us all, he goes into detail on all the challenges and solutions he faced.

When we covered the original TurtleAuth DIY security token, everything worked fantastically. However, the PCB layout had a few issues that became apparent after a year or so of daily use. Rather than 3D print an enclosure and call it done, [Samuel] decided to try a different idea and craft an enclosure from the PCB layers themselves.

The three-layered PCB sandwich keeps components sealed away and protected, while also providing a nice big touch-sensitive pad on the top, flanked by status LEDs. Space was a real constraint, and required a PCB redesign as well as moving to 0402 sized components, but in the end he made it work. As for being able to see the LEDs while not having any component exposed? No problem there; [Samuel] simply filled in the holes over the status LEDs with some hot glue, creating a cheap, effective, and highly durable diffuser that also sealed away the internals.

Making enclosures from PCB material can really hit the spot, and there’s no need to re-invent the wheel when it comes to doing so. Our own [Voja Antonic] laid out everything one needs to know about how to build functional and beautiful enclosures in this way.

The microcontroller described in the article, on the PCB taken out of the kettle

Dumping Encrypted-At-Rest Firmware Of Xiaomi Smart Kettle

May 4, 2022 by Arya Voronova 52 Comments

[aleaksah] got himself a Mi Smart Kettle Pro, a kettle with Bluetooth connectivity, and a smartphone app to go with it. Despite all the smarts, it couldn’t be turned on remotely. Energized with his vision of an ideal smart home where he can turn the kettle on in the morning right as he wakes up, he set out to right this injustice. (Russian, translated) First, he tore the kettle down, intending to dump the firmware, modify it, and flash it back. Sounds simple enough — where’s the catch?

This kettle is built around the QN9022 controller, from the fairly open QN902X family of chips. QN9022 requires an external SPI flash chip for code, as opposed to its siblings QN9020 and QN9021 which have internal flash akin to ESP8285. You’d think dumping the firmware would just be a matter of reading that flash, but the firmware is encrypted at rest, with a key unique to each MCU and stored internally. As microcontroller reads the flash chip contents, they’re decrypted transparently before being executed. So, some other way had to be found, involving the MCU itself as the only entity with access to the decryption key.

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You Break It, We Fix It

February 26, 2022 by Elliot Williams 45 Comments

Apple’s AirTags have caused a stir, but for all the wrong reasons. First, they turn all iPhones into Bluetooth LE beacon repeaters, without the owner’s permission. The phones listen for the AirTags, encrypt their location, and send the data on to the iCloud, where the tag’s owner can decrypt the location and track it down. Bad people have figured out that this lets them track their targets without their knowledge, turning all iPhone users into potential accomplices to stalkings, or worse.

Naturally, Apple has tried to respond by implementing some privacy-protecting features. But they’re imperfect to the point of being almost useless. For instance, AirTags now beep once they’ve been out of range of their owner’s phone for a while, which would surely alert the target that they’re being tracked, right? Well, unless the evil-doer took the speaker out, or bought one with the speaker already removed — and there’s a surprising market for these online.

If you want to know that you’re being traced, Apple “innovated with the first-ever proactive system to alert you of unwanted tracking”, which almost helped patch up the problem they created, but it only runs on Apple phones. It’s not clear what they meant by “first-ever” because hackers and researchers from the SeeMoo group at the Technical University of Darmstadt beat them to it by at least four months with the open-source AirGuard project that runs on the other 75% of phones out there.

Along the way, the SeeMoo group also reverse engineered the AirTag system, allowing anything that can send BLE beacons to play along. This opened the door for [Fabian Bräunlein]’s ID-hopping “Find You” attack that breaks all of the tracker-detectors by using an ESP32 instead of an AirTag. His basic point is that most of the privacy guarantees that Apple is trying to make on the “Find My” system rely on criminals using unmodified AirTags, and that’s not very likely.

To be fair, Apple can’t win here. They want to build a tracking network where only the good people do the tracking. But the device can’t tell if you’re looking for your misplaced keys or stalking a swimsuit model. It can’t tell if you’re silencing it because you don’t want it beeping around your dog’s neck while you’re away at work, or because you’ve planted it on a luxury car that you’d like to lift when its owners are away. There’s no technological solution for that fundamental problem.

But hackers are patching up the holes they can, and making the other holes visible, so that we can at least have a reasonable discussion about the tech’s tradeoffs. Apple seems content to have naively opened up a Pandora’s box of privacy violation. Somehow it’s up to us to figure out a way to close it.

Pixelating Text Not A Good Idea

February 23, 2022 by Al Williams 63 Comments

People have gotten much savvier about computer security in the last decade or so. Most people know that sending a document with sensitive information in it is a no-no, so many people try to redact documents with varying levels of success. A common strategy is to replace text with a black box, but you sometimes see sophisticated users pixelate part of an image or document they want to keep private. If you do this for text, be careful. It is possible to unredact pixelated images through software.

It appears that the algorithm is pretty straightforward. It simply guesses letters, pixelates them, and matches the result. You do have to estimate the size of the pixelation, but that’s usually not very hard to do. The code is built using TypeScript and while the process does require a little manual preparation, there’s nothing that seems very difficult or that couldn’t be automated if you were sufficiently motivated.

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How A Pentester Gets Root

February 20, 2022 by Donald Papp 9 Comments

Have you ever wanted to be a fly on the wall, watching a penetration tester attack a new machine — working their way through the layers of security, ultimately leveraging what they learned into a login? What tools are used, what do they reveal, and how is the information applied? Well good news, because [Phani] has documented a step-by-step of every action taken to eventually obtain root access on a machine — amusingly named DevOops — which was set up specifically for testing.

[Phani] explains every command used (even the dead-end ones that reveal nothing useful in this particular case) and discusses the results in a way that is clear and concise. He starts from a basic port scan, eventually ending up with root privileges. On display is an overall process of obtaining general information. From there, [Phani] methodically moves towards more and more specific elements. It’s a fantastic demonstration of privilege escalation in action, and an easy read as well.

For some, this will give a bit of added insight into what goes on behind the scenes in some of the stuff covered by our regular feature, This Week in Security.

This Week In Security: Zimbra, Lockbit 2, And Hacking NK

February 11, 2022 by Jonathan Bennett 9 Comments

Unknown attackers have been exploiting a 0-day attack against the Zimbra e-mail suite. Researchers at Volexity first discovered the attack back in December of last year, detected by their monitoring infrastructure. It’s a cross-site scripting (XSS) exploit, such that when opening a malicious link, the JavaScript running on the malicious page can access a logged-in Zimbra instance. The attack campaign uses this exploit to grab emails and attachments and upload them to the attackers. Researchers haven’t been able to positively identify what group is behind the attacks, but a bit of circumstantial evidence points to a Chinese group. That evidence? Time zones. The attacker requests all use the Asia/Hong_Kong time zone, and the timing of all the phishing emails sent lines up nicely with a work-day in that time zone.

Zimbra has responded, confirming the vulnerability and publishing a hotfix for it. The campaign seems to have been targeted specifically against European governments, and various media outlets. If you’re running a Zimbra instance, make sure you’re running at least 8.8.15.1643980846.p30-1.

LockBit 2.0

Because security professionals needed something else to keep us occupied, the LockBit ransomware campaign is back for a round two. This is another ransomware campaign run in the as-a-Service pattern — RAAS. LockBit 2 has caught enough attention, that the FBI has published a FLASH message (PDF) about it. That’s the FBI Liaison Alert System, in the running for the worst acronym. (Help them figure out what the “H” stands for in the comments below!)

Like many other ransomware campaigns, LockBit has a list of language codes that trigger a bail on execution — the Eastern European languages you would expect. Ransomware operators have long tried not to poison their own wells by hitting targets in their own back yards. This one is being reported as also having a Linux module, but it appears that is limited to VMWare ESXi virtual machines. A series of IoCs have been published, and the FBI are requesting any logs, ransom notes, or other evidence possibly related to this campaign to be sent to them if possible. Continue reading “This Week In Security: Zimbra, Lockbit 2, And Hacking NK” →

Long Range Burglar Alarm Relies On LoRa Modules

January 28, 2022 by Lewin Day 15 Comments

[Elite Worm] had a problem; there had been two minor burglaries from a storage unit. The unit had thick concrete walls, cellular signal was poor down there, and permanent wiring wasn’t possible. He thus set about working on a burglar alarm that would fit his unique requirements.

An ESP32 is the heart of the operation, paired with a long-range LoRa radio module running at 868 MHz. This lower frequency has much better penetration when it comes to thick walls compared to higher-frequency technologies like 4G, 5G or WiFi. With a little coil antenna sticking out the top of the 3D-printed enclosure, the device was readily able to communicate back to [Elite Worm] when the storage unit was accessed illegitimately.

With an eye to security, the device doesn’t just warn of door open events. If signal is lost from the remote transmitter in the storage unit, perhaps due to an advanced adversary cutting the power, the alarm will also be raised. There’s still some work to be done on the transmitter side, though, as [Elite Worm] needs to make sure the door sensor is reliable under all conditions.

Many put their hardware skills to work in service of security, and we regularly see proprietary alarm systems modified by enterprising hackers. Video after the break.

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