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How To Use A Bitcoin Hardware Wallet
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Major exchange Coinbase has announced it will begin to supporting crypto hardware wallets, starting with Ledger. The two companies made the announcement at the Ledger Open conference, which is taking place in Paris on Dec 9 and 10.
Ledger is a major supplier of cold hardware wallets, which store users’ private keys more securely than hot online wallets.
Users of the Coinbase Wallet browser extension will be able to connect their Ledger hardware wallets, maintaining self-custody and full controlover their assets.
The partnership will be rolled out in phases, starting in the first quarter of 2022. Further down the track, the Coinbase mobile app will also support Ledger hardware wallets.
Max Branzburg, VP of Product at Coinbase said: “we’re excited to share more announcements on how we’re making Coinbase Wallet the safest and most secure way to participate in Web3 over the coming months.”
Meanwhile, Coinbase CFO Alesia Haas made some big statements in her testimony to the U.S. House Committee on Financial Services on Dec 8. She claimed that Coinbase stores about 12% of all crypto across more than 150 asset types and said crypto was moving beyond simple coin swaps.
“Nearly 50% of our transacting customers are doing something other than buying and selling crypto, which indicates to us that crypto is moving beyond its initial investment phase into the long expected utility phase,” she said.
Related: Why hardware wallets might not offer as much protection as you think, explained
Coinbase claims to have over 73 million customers globally, including 10,000 institutions and 185,000 application developers.
SeedSigner is the new, cool kid on the block when it comes to DIY Bitcoin hardware wallets. It’s a very interesting device that certainly does things differently compared to the other hardware wallets on the market.
Highlights include:
SeedSigner’s initial commit
The project was “born” on December 14, 2020, but it started getting most-deserved attention recently.
Let’s start from zero and work our way to using the device so we can see what’s all the fuss about:
SeedSigner Bitcoin hardware wallet components
Everything in the picture set me back around $100. It’s worth mentioning that I did not try to get the cheapest options, but the fastest ones, and some of the components were overpriced. I also went for the expensive case that was $35, the cheaper one goes for $10. You should be able to get the costs of materials down to $50.
After you get all of the components, we will need to download the operating system and burn it to the SD card.
SeedSigner uses a modified version of Debian for Raspberry Pi. Debian is a Linux distribution that only uses free and open-source software (FOSS). You can get the latest release here.
After we get the archived .IMG file, we need to verify it. The file is signed by the maintainer of the project, and we will use their credential to verify the integrity of the file. For this, we will be using GPG, which is a program that allows us to import the authors public keys and verify signatures. This is present on all Linux operating systems and Mac (which is also based in Linux). If not, you can get it here.
Now, we need SeedSigner’s GPG public key.
The maintainer has the key listed in multiple places. “Why?,” you ask?
Well, we are trying to make sure an attacker did not replace the file we want to burn on the SD card with a malicious one, but if an attacker would be successful in compromising the place from which we get the files, of course, they would also change the public key with their one, so we can’t tell the file is fake.
That’s why you should always check the key in multiple places.
You can find the key:
So, we will open a terminal and type in:
curl -sS https://raw.githubusercontent.com/SeedSigner/seedsigner/main/seedsigner_pubkey.gpg | gpg –import
Now that we have the key imported into our keychain, let’s get the files from:
https://github.com/SeedSigner/seedsigner/releases
We will get two files:
The next command we will run will confirm the integrity of the file:
gpg –verify seedsigner_0_4_4.img.zip.txt.gpg
We are looking for “good signature.” This is a confirmation that everything is ok.
Now that we know the .IMG is real, we can write it to the SD card. For this, I use balenaEtcher, a software that allows you to burn the .IMG file to the SD card. It is pretty straight forward and you can use drag and drop.
Also, download this template here and print it out, it will be useful later.
Now comes the fun part.
Insert the solder-less Hammer Header in the GPIO pins. Apply pressure until they are in.
Even though this adds a bit to the cost of the device, it could still be worth it if you don’t already have a soldering iron and solder, and if you don’t plan to solder anything else in the future.
Also, fuck you soldering iron.
Insert the wide side of the ribbon cable (the one shaped like a trapezoid) into the AuviPal 5MP camera. Make sure the shiny contacts face the green circuit board.
Now, take the narrower part of the ribbon cable and attach it to the Raspberry Pi Zero. The same thing as before: shiny contacts need to face the green circuit board.
Now, take the bottom part of the case and fit the camera in the camera holder. Use a bit of pressure until you hear a click.
This is how it should look from behind:
Insert the SD card in the Pi. Then, gently place the Pi over the camera. Orient the Pi so that the ports fit in the port grooves.
Place the 10 mm F-F M2.5 spacer over the holes in the front.
Insert and tighten the 12 mm M2.5 pan-head screws from behind.Repeat for all four holes.
Repeat for all four holes.
Insert the Waveshare 1.3-inch IPS LCD display into the GPIO pins.
The process should be very easy and straightforward as there is the same number of holes in the display as there are pins.
Using the four remaining 6 mm M2.5 pan-head screws, secure the display by screwing in the 10 mm F-F M2.5 spacers.
Snap the bottom and upper parts together.
And now the assembly is done.
Before anything else, we need to plug the SeedSigner into a power source. The whole idea behind SeedSigner is that it’s an air-gapped device, meaning that it’s isolated from any internet connection, this is where most of the security comes from.
The Raspberry Pi Zero has two ports, and the most left one only allows power, so it’s perfectly safe to plug this into the USB of your computer if it’s easier.
Don’t worry if you don’t see anything on the screen, the device takes about 45 seconds to boot up.
We have two options available to generate a BIP39 seed:
Both of these methods are great sources of entropy as they don’t depend on specialized hardware. Most of the devices we use have special hardwares that are used as sources of entropy, but most of them can’t really be audited, and this creates a big attack vector. And even if someone does not try to mess with them, there could be bugs.
This BYOE approach is great as it completely eliminates these worries.
Good entropy (from a cryptographical POV) means that no one else can reproduce what you did, and the picture and a successive set of 99 rolls of dice are really good for this.
We will be using the picture mode here, as it’s quite easy to do and takes less time:
In the menu, go to “Seed Tools,” then “Generate Seed With Image.” Point the camera at something and press the joystick. If you’re happy with the picture click “Accept.”
Now, take the template and write down the BIP39 words. Using a pencil is preferred, as it withstands the test of time better (scroll right with the joystick to advance).
After scrolling past the seed words you will see a QR code on the screen. The QR encodes the words in a more compact way that is easy to read for computers. Even though it’s not tangible for humans, it’s a great way to transfer information between devices and it has error correction.
You transfer the exact amount of information you want, which allows us to keep the device air gapped and avoid any malware being transmitted during communication.
By pressing on the joystick, you will be taken into zoom mode. Here you can use the joystick to navigate and the X and Y coordinates help you identify where you are on the QR code. Notice that this is the same as the QR present on the template.
You will start from position A1 (that’s the upper-most left corner) and work your way around the QR. Again, I suggest using a pencil, as graphite is resistant to ultraviolet radiation, moisture and other chemicals, making it great for long-term storage solutions.
Here is a speed-up video of me transcribing the BIP39 seed that’s encoded in a QR code to the template we downloaded earlier:
When done, click “Save Seed.”
As the saved seed is completely non-persistent, meaning it does not store any information on the device, you will need to import your seed every time you want to make a transaction. You can store the seed temporarily, but it will be wiped once the device reboots.
Next, we need to import the xPub on our computer. This will give us access to all of the addresses to receive funds in the future and check the stash without connecting the device. We can generate any addresses we want in the future so we can receive funds, while the seed remains safe on the paper.
We will set up the wallet for single-signature use.
In the menu, go to “Settings,” then “Script Policy,” then select “Single Sig Native SegWit.” Then return to the main menu. Then go to “Seed Tools,” then “xPub From Seed.” Use the saved seed. Check if the words match with the backup and pick “Sparrow Wallet.”
You will be presented with a QR code on the SeedSigner — this is the xPub that we will import on the computer.
We will be using Sparrow Wallet.
By the way, my favorite Bitcoin app has been Electrum since the first day I got into Bitcoin. It’s the Swiss Army knife light Bitcoin wallet that allows me to use my own server.
But Sparrow is a better version of that, which also looks and feels very cool. You can get it here.
In Sparrow Wallet, on your computer, create a new air-gapped hardware wallet. Click the “Scan” button next to the SeedSigner icon and present the QR from the SeedSsigner to your camera. When the QR is recognized, the details will be filled in.
Set a password, and we can receive some coins.
Don’t worry if something does not make sense, you can get back to it later.
Next, we are going to receive some bitcoin.
We can get a new address by clicking “Get Next Address” or selecting one from the “Addresses” tab. The imported xPub allows the computer to calculate all of the addresses that belong to the specific BIP39 seed.
In the video, I am sending 0.0001 BTC from the “Trendon Shavers” (imagine this is another person) wallet to the SeedSigner wallet. This is a hot wallet set up on the computer.
Notice that in order to get a new address, we did not need access to the SeedSigner.
Now we will be using the device for what it was created for, QR signing.
By the way, the person behind the SeedSigner Twitter handle and the main maintainer of the project prefers the terminology “optical air gap signing” (pretentious bastard).
Now we will be sending the coins back to the same address we received them from.
In Sparrow Wallet, we paste in the destination address and the amount, and the fee as we would do in any “normal” Bitcoin wallet, and then we create the transaction. The way Bitcoin works is that the construction of the transaction and the signing are separate steps. Usually wallets abstract this away as they prioritize user experience.
If we try to broadcast the transaction without signing it, the nodes will not find a valid signature and will not allow the coins to be spent, so we need to produce a signature. We want to get the unsigned transaction on to the SeedSigner so it can sign it, and we will of course use QR codes again.
There is something different about these QR codes; they are animated. Why? Well because they need to send more information.
Imagine that you have someone using sign language to communicate with someone else. If they want to say a long sentence, they need multiple signs, one after the other. In order to produce a signature, we need to use the private keys, which we have backed up on the paper in the form of a QR that represents the BIP39 words.
First, we will import the seed in the SeedSigner using the QR code we have on paper. While doing so, we double-check to make sure the words match.
After this, we will be asked to scan the PSBT QR (PSBT stands for “partially-signed Bitcoin transaction,” which is what the animated QR represents). Now, we point the SeedSigner at the computer screen. As soon as this is done, we are asked to confirm the details of the transaction.
After the confirmation, the SeedSigner signed the transaction (serving its existential purpose) so now we have to pass the signed transaction back to the computer to broadcast it.
Of course, we will use an animated QR code again, but this time, we will be scanning with the camera of the computer from the SeedSigner. After that is done, we click “Broadcast” and we see the transaction showing up on the block explorer.
Don’t worry if this is a bit confusing, I promise you after you do it yourself once, it’s less intimidating.
The biggest selling point in my opinion is that the SeedSigner uses general-purpose hardware.
Hardware wallets are a great invention, and for almost anyone, they increase the security of their bitcoin stash by 100-times compared to using your phone or computer. This is done by eliminating components that are not strictly needed for Bitcoin signing operations (software and hardware) and by segregating the device (some more than others) from the internet and other devices.
But in order to deliver such a device and enforce these restrictions, this means you have to create a device that’s designed for this specific purpose, meaning that this makes it an easy target for an attacker.
It’s pretty obvious that a Bitcoin device will be used for Bitcoin stuff, but these third-party attacks can range in different ways.
Your device can be intercepted and an attacker can plant things on it that could transmit information on the device or screw with the seed generation or even mess with the transaction creation process so that you send the coins to their address instead of your own. There have been multiple attempts to solve this problem, but I don’t think any of them offer a real solution.
For example, a lot of hardware wallets seal the bags in which they save the device. These are trivial to open and reseal. If anything, they offer a false sense of security. (I do want to mention that the only real solution in this direction is offered by https://www.entropyseal.com/, but the product is currently just a prototype).
The hardware used for these devices can also be targeted in the factoring process or before that, to implement any variants of the above-mentioned attacks. The truth is that even auditing the device is not as easy as you may think, even though wallets like the ColdCard try to mitigate these problems (through a transparent case and the use of a green light to give the ok on the firmware)
Now, these may seem a bit like tinfoil-hat things, but they are real concerns, and as bitcoin rises in price, the chance and incentive for them to happen scales proportionally.
Aaaanyway, all of these worries are eliminated when you buy hardware that can be used for anything.
The chance of someone knowing that you will use a Raspberry Pi Zero, which is used for 10,000 other things, as a Bitcoin hardware wallet is almost zeo. I think people in the space have got to a point where they think that hardware wallets are silver bullets and they don’t realize that all of that security you get comes with tradeoffs
Your private key is entropy. Entropy means randomness, disorder, and the reason why these are important properties for the private keys is that if someone wants to guess the keys, the only solution is to go through all of the possibilities of private keys that there are. And trust me, there are a lot — 2^256 or about as many atoms there are in the visible universe.
This is what we call needle-in-haystack technology.
The topic of entropy is very vast and deserves an article of its own (maybe a video of its own, follow me at https://twitter.com/raw_avocado), but usually, we have some specific hardware dedicated to this purpose. Most of this hardware is not auditable, and even though on paper some of them are open, you can’t really check under the hood and see what you got there.
The SeedSigner again eliminates this worry completely by only allowing you to use your own entropy. The dice rolls option is also supported by the ColdCard and is a great way of adding this security, but it is a bit time consuming. The picture option also is great, as it’s almost impossible to get the same picture two times.
Even though it might look like two pictures are the same to you, they are not. Even the smallest variations in light and angle will result in a separate picture. On top of that, all of the cameras also detect small radiations that are truly random and thus add to the total entropy of the picture.
Most of the hardware wallets use microcontrollers, which means that they are very small computers that have most of their components under one single chip. As you can imagine, these computers are very dumb and weak, but this lowers the attack surface. Also, most of the hardware wallets run the programs that do the Bitcoin operations straight on the bare metal.
As I mentioned, the device takes 45 seconds to boot up and this is because it needs to boot up a full operating system the same as your laptop. The SeedSigner uses the RaspberyPi version of Debian, which, even though it is a stripped-down version of Debian, still has a lot of things inside of it, which means attack surfaces.
It’s worth mentioning that the whole philosophy behind Debian is to use only free and open-source software. The device is of course completely air gapped, so these attacks are kind of nullified. But it still adds to big boot time.
There are conversations regarding easy improvements of the boot time, and someone is even working on a custom Kernel, so keep an eye out for this.
The Bitcoin stuff added on top of the OS is very minimal and is written in Python, and uses well-reviewed libraries, and includes very minimal code, which makes it pretty easy to look through and see how the sausages are made (this coming from someone who is not a developer).
Navigation on the device is a bit clunky and I would love to see the use of the right buttons, as that feels the natural way to use the device. Also, I would like to jump back and forward between menus using the joystick.
This could be a very easy fix and it will be present in future updates. Developer Keith Mukai is already working on a new user interface for the menu, which is currently tested.
Even though this is a security product, user experience is still crucial. If the solution is too inconvenient, it will not be used by anyone, or even put people off while they try it.
The transcribing of the QR code took me literally one full hour. Truth be told, it would have gone faster if I used a Sharpie, but as I mentioned, that’s not the best for long-term storage. Some people use a Sharpie and then vacuum seal the paper, but that’s just another level of inconvenience and requires additional stuff, so no thanks.
Some people told me that they nailed the process with a Sharpie down to five minutes after practice. But if you need to practice to get this going, then this is a bad process from the start.
I honestly feel that this is a solution for a problem that should not exist in the first place. The Raspberry Pi Zero does not have any storage device, so there is no place to store the device except on the SD card, which is used to run the OS. I do know they are also working on improving this and allowing for SD card backups, so stay tuned.
Mukai is the one who came up with this idea to encode the BIP39 seeds as a QR code, and you have to admit this is a pretty clever and creative idea. And considering where the project currently is, it definitely makes things better than the alternative of importing it using the virtual keyboard.
But, compared to the other hardware wallets, it’s not 10-times better, which is how I judge things when I see a new product on the market. A plain-text electronic backup is better than a plain-text paper backup, as even if you have the seed in plain text on the SD card, you still need the additional step to insert the SD card into a computer in order to read it, nevermind the fact that you can encrypt it.
This is not something to worry about, but it’s something I noticed, and I thought I’d mention it, as the device is advertised as stateless:
If you plug out the power supply while the QR is visible on the screen when powering it up again, during the 45-second boot you can see the residue of the QR. It’s worth noting that this is not the proper way to turn off the device, as it has a full OS running on it. That’s why there is a shutdown option from the menu.
But if I naturally did this, I can imagine other people will also. This of course only “leaks” your xPub, so it can be just a privacy concern if anything, and again someone needs to have your device for this to be the case, so not a major issue.
When I brought this up in the SeedSigner Telegram group, it turned out it was a known issue, and there is a fix for it: a screensaver. Mukai strikes again.
Even though I had some criticisms of the SeedSigner, I still think it’s a great device and offers a good and new set of trade-offs.
The device is recommended to be used as one or more signatures of a multisig setup and the whole point is to use different devices from different vendors with different tradeoffs and risks, and the SeedSigner brings this variety.
Looking at how the project evolved, I see a good trajectory and want you to keep in mind that this is a very young project. The fact that the project combines general-purpose hardware and BYOE makes this device very attractive to me and screams trust minimization, and no targeted third-party attacks.
All of the interactions I had with people working on the project were great. And by that, I don’t mean nice (which they also were), as that does not really matter. I mean that every concern and question I had was always answered in a straightforward and honest manner. That matters a lot for me.
The device is perfect for someone who is a relative beginner and wants to learn how Bitcoin works under the hood. The project is very easy to put together, and because all of the steps in a transaction are broken up, you get to do them separately and manually — you get to look under the hood.
Anyway, let me know what you thought about my review and if you have any trouble while making your own, you can shoot me a DM on Twitter, but I suggest also checking out the Telegram group.
This is a guest post by Alex Waltz. Opinions expressed are entirely their own and do not necessarily reflect those of BTC Inc or Bitcoin Magazine.
On April 4, 1933, probably only a handful of Americans were prudent enough to hold gold coins in their homes. There seemed to be nothing wrong with keeping the gold safe in the banks, after all. All of this changed a day later when President Roosevelt announced Executive Order 6102, “forbidding the hoarding of gold within the continental United States.” Whoever trusted third party providers for their security and privacy suddenly found themselves rug-pulled. Only those with a healthy mistrust of the government and custodians had the power of choice. They could comply with the confiscatory order or they could hold on to their property.
That’s what privacy is all about, after all: maintaining the option to decide for yourself, not having others decide for you.
Privacy is one of those things that you don’t really value until you lose it.
The present-day lack of concern for financial privacy is mostly a result of long-term conditioning. When it comes to financial matters, privacy has been demonized for a better part of a century now.
The coordinated attack on financial privacy began in the 1930s, during the U.S. alcohol prohibition. This nonsensical prohibition created a new type of risk-prone entrepreneur: the gangster. At the time, it was a struggle to prosecute gangsters in any conventional way, so the government pushed banks to inquire about their clients’ source of income. Those who couldn’t explain their earnings were charged with tax evasion. That’s how Al Capone ended up in jail.
Prohibition ended in 1933 but the foundation for the regime of financial surveillance remained. In the following decades, it was expanded in the name of wars on drugs and terror (both very questionable in their results and brutal in terms of collateral damage). Though the arguments for financial surveillance change over the years, there is one underlying motive for eliminating financial privacy: ensuring there is no escape from the tax regime. The tax Leviathan is an ever-hungrier beast that consumes everything in its wake. And it doesn’t recognize fair play.
The state sets the rules and the rules can change overnight. You can reassure yourself with, “it doesn’t happen here” — until it does. Who in 1933 expected that a civilized state like the U.S. would simply steal from its citizens via an executive order? In times of turmoil, national laws can change quickly and usually to citizens’ disadvantage. What is perfectly legal, such as holding your own gold coins or Bitcoin private keys, can be declared against the law in the future.
And we are living in times of turmoil right now. This is the end of the line for the 50-year-old experiment of pure fiat. The interest rates are staying at zero. The quantitative easing, the Fed repo operations, the stimulus checks — all here to stay. Without these programs the debt-addicted economy falls apart like a house of cards. The next move to keep it standing will involve the Orwellian construct that is central bank digital currencies.
And your bitcoin will be both a dangerous subversion of such an attempt and a lucrative target for taxation or confiscation (as if there really was a difference).
Privacy is an insurance policy against desperation, both of the private and public kind. But while you can legally protect yourself against the private thieves, it’s impossible to do so against the public ones. Your only mode of protection is ex ante, before the event. In other words, your only mode of protection is keeping yourself under the radar.
Privacy with Bitcoin is possible, but not by default. Bitcoin privacy works in the same way as Bitcoin security, in the sense that it’s ultimately up to you. There are tools, education resources, and people ready to answer questions; but you have to dedicate your time and take the necessary steps yourself.
The first thing to realize is that there is no silver bullet for privacy. No single app, wallet, setting or process will ensure your privacy in one easy step and for eternity. Privacy is a mental state. You have to want it and act accordingly on an ongoing basis.
Privacy is also a spectrum. There are many steps between transparency and anonymity. It’s desirable to make at least a small move away from complete transparency, even if you can’t achieve full anonymity. Don’t be the lowest hanging fruit.
The most powerful privacy tool is your mind and your mouth.
Most of us have made some mistakes when it comes to Bitcoin privacy: we bought from a shady exchange that now holds our personal data, we reused addresses, we merged coins that should have been kept separate and so on. Realizing these mistakes and searching for ways to mitigate them is the first step. Being aware of how to avoid any future mistakes is the next one.
But it’s crucial to remember that you can do everything right from a technical perspective and later undo the privacy gains simply by talking too much. You may have the best Shamir scheme set up, but how safe will it be if you blabber about it on a pub crawl?
Does that mean you shouldn’t evangelize Bitcoin to your friends and family? Not at all. Just remember that there’s a huge difference between talking about Bitcoin in general and talking about your bitcoin.
Make a strict mental line: questions about Bitcoin’s features and best practices are relevant, while questions about your personal stash, seed location or stacking strategy are not.
That being said, let’s dive into some practical tips for improving your Bitcoin privacy.
Keeping bitcoin “clean” is a bit like taking care of your fancy clothes; while it’s good to know proper laundry techniques, it’s better not to get it stained in the first place. In the case of bitcoin, KYC is the stain. KYC stands for “know your customer,” a mandatory identification procedure that service providers (e.g. exchanges) have to perform on their clients.
There are two risks to your privacy when it comes to KYC.
This first risk arises from the transparent nature of Bitcoin’s blockchain. When you buy bitcoin on a KYC exchange and withdraw, the exchange operators are aware of your withdrawal address and can easily track your subsequent transactions. This also goes for any third parties with whom they share this information, such as government bodies. This particular risk can be mitigated by utilizing CoinJoin and coin control, where you mix coins with other users and keep track of where you got particular coins from and where you’re spending them next. Tools like Wasabi Wallet help a great deal with that. However, be aware that if you choose to improve your privacy through CoinJoin, some exchanges may view that as suspicious and refuse to accept your coins.
The second risk arises from the process of identification itself. If you buy on a KYC exchange, you will simply be known as a person that has acquired bitcoin in the past. This could be misused by criminals who may target you based on leaked user data. This information could also be used by the government in the future if the laws concerning personal bitcoin holdings change, a new tax on bitcoin holdings is enacted and so on. The only way to truly mitigate this risk is by selling the same amount of bitcoin you’ve previously bought and rebuying in a more private manner (peer-to-peer or bitcoin ATM, preferably for cash). This way you’ll have a record of not holding any bitcoin anymore. Note that selling may carry tax consequences. The other option is the “boating accident” excuse where you claim that you’ve lost the keys, your dog ate the recovery seed, etc., though this may carry unknown risks.
At the fundamental level, bitcoin exists in the form of discrete unspent transaction outputs (UTXOs). A UTXO is an amount of bitcoin that lies on your address as a result of a previous transaction. The UTXO is what the observer — an exchange, a chain analysis company — tracks and analyzes to build a graph of who owns which coins and where they have moved over time.
UTXO management can get tricky because you have to keep in mind that there is a difference between a UTXO, an address and a wallet.
Addresses are where the UTXOs are kept. You should only have one UTXO per address, meaning you should never reuse an address to receive multiple transactions. Address reuse helps the observer to link various coins to one entity. Avoiding address reuse is easy: your wallet knows which addresses already have UTXOs and which don’t; when you click “receive,” it will always give you an unused address.
A wallet holds your unique private key and its corresponding public keys which, in turn, determine the addresses controlled by that wallet. Be aware that even if you never reuse addresses and thus keep the UTXOs separated, you can still inadvertently link your UTXOs. If you attempt to send a 0.1 BTC payment but no single UTXO has that much value, your wallet will automatically combine multiple UTXOs in order to assemble the total target amount. Once this multi-input transaction is sent, the observer can see that the previously unconnected UTXOs were in fact owned by one entity.
You can set up multiple accounts in your wallet as long as it supports BIP32. This is especially useful if you have both KYC’d and non-KYC’d coins. By keeping them separated in different accounts, they will never be mixed in a multi-input transaction.
The more advanced solution is to label your individual UTXOs and select specific UTXOs for each transaction. This is known as coin control. This is currently possible with wallets like Electrum, Samourai, Specter Desktop or Wasabi. Hardware wallet vendors maintain their own wallet software and support for coin control varies: it’s available as an advanced option in Ledger Live and Trezor Suite is planning to include this feature in November 2021. You don’t have to use your wallet vendor’s software; all of the major software wallets support all of the major devices. However, using the vendor software has its advantages in the form of high quality UX, professional customer support, security updates and gradual rollout of duly tested features like masking your IP address via Tor or bumping transaction speed through replace-by-fee (RBF).
Even if you never buy through a KYC exchange and keep your UTXOs neat and shiny, you and your coins can still be linked together via your IP address. You can use a VPN service to obfuscate your location, but such services are still based on a trust assumption (you trust the service providers to not keep activity logs).
Using Tor is a better practice. Think of it as a kind of trustless VPN where there’s no one on the other end who can track your activity. Advanced wallets usually come with the option of routing all the traffic through Tor. For example, Trezor users simply have to turn the Tor Switch on in the Trezor Suite.
Concealing your IP address is especially important when you run your own Bitcoin node because that node advertises your IP address to the world.
When you connect to somebody else’s node, they can see all of the transactions you submit through them. When you look up your address balances or transaction details on a public block explorer, the operator can see that as well. When combined with an unobfuscated IP address, this can have serious privacy consequences.
The solution is to run your own node and, ideally, also a block explorer on top of it. You can either set up everything yourself with Bitcoin Core software, or you can go for one of the all-in-one products that set up a node for you and allow you to easily set up BTCPay Server or manage your Lightning Node (LN) and LN channels.
The Lightning Network deserves at least some mention in an article on Bitcoin privacy. The common misconception is that Lightning payments are anonymous because they leave no blockchain trail. First of all, that’s only partially true. The prerequisite for a Lightning payment is an open payment channel, which first requires an on-chain transaction to take place. So if an observer has the UTXO and the identity already linked, they also know who owns the channel.
Channel openings aside, there are privacy concerns on the Lightning Network itself. While senders are quite private, recipients reveal quite a lot through their node IDs and invoices.
If you’re more interested about privacy on the Lightning Network, I highly recommend reading through Anthony Ronnings’s Current State of Lightning Network Privacy.
There are many aspects to privacy when using Bitcoin. This article barely scratches the surface of the various pitfalls and possible mitigations. There is no single solution that will protect your privacy, but rather each of us must routinely question if the actions we are taking will negatively impact our privacy. It is dangerous to be complacent about privacy — any information you share can be used to attack you or otherwise make you powerless, regardless of how safe you feel now. The key takeaway is this: be aware of the need for your financial privacy, make it a habit to learn about privacy and use the tools that are available to you to protect it.
This is a guest post by Josef Tětek. Opinions expressed are entirely their own and do not necessarily reflect those of BTC, Inc. or Bitcoin Magazine.
Bitcoin hardware wallet manufacturer Foundation Devices has raised $2 million in a seed round led by venture fund Bolt.
Foundation Devices, a bitcoin hardware wallet manufacturer, has announced it has raised $2 million in a seed round led by early-stage venture fund Bolt. Along with the round, Tyler Mincey, a partner at Bolt who previously worked at Apple, will join the Foundation board.
“Foundation is building the open hardware foundation for Bitcoin and a decentralized internet,” the manufacturer stated in the announcement. “We believe that a new internet, powered by open-source software, must run on open hardware. Our goal is to build a new category of sovereign computing to serve as an open platform for development of a decentralized internet.”
The hardware wallet manufacturer began shipping its first product, Passport, last month. With the seed round, Foundation plans to improve Passport with firmware updates and design enhancements and launch a companion software for the product.
In addition, the company has started expanding its team, which up to this point consisted only of its four cofounders. Foundation is looking for engineers in the software and mechanical fields, designers, and people to staff customer support and social media.
Existing investors Warburg Serres, Fulgur Ventures and Inflection also participated in the seed round, along with new investors Third Prime, Massachusetts Avenue Capital, Unpopular Ventures and Deep Ventures.
Foundation Devices CEO Zach Herbert has a stated focus on providing open-source hardware wallets, aiming to empower individuals to use and store bitcoin while maintaining their sovereignty. According to Herbert, Foundation’s Passport is assembled in the U.S. and based on open-source code from Coldcard and Trezor.
Earlier today, Prague-based crypto security startup Tropic square, a subsidiary of SatoshiLabs, announced that it received a 4 million euro (about $4.776 million) investment to propel its work on the first-ever open-source security chip. The funding came from Swiss investment company Auzera.
“The chip, code named TASSIC (Transparent Authenticated Secure Storage Integrated Circuit), is expected to be introduced by the end of 2022, and it is already clear that it will be used in one of the most popular crypto hardware wallets Trezor, also made by SatoshiLabs,” according to a Tropic Square press release sent to Bitcoin Magazine.
SatoshiLab’s users community had been requesting a secure element chip inherently designed to prevent unauthorized access and protect sensitive data. The closed-source security chips that are often used in hardware wallets can be viewed as vulnerabilities in the custody of bitcoin, as the community cannot audit a critical piece of security that is protecting their funds. But the use of an open-source security chip could very well have applications outside of bitcoin as well.
“The initial motivation for the whole project was the need for a microprocessor solution for Trezor. However, thanks to the closed source settings of the chip manufacturers, we couldn’t find an ideal solution,” Marek Palatinus, CEO of SatoshiLabs, per the release. “We believe that this revolutionary chip can succeed outside the realm of cryptocurrencies.”
According to the release, manufacturers of security chips force their clients to sign non-disclosure agreement contracts. Hence, if the manufacturers’ users discover a problem, it becomes legally impossible for them to take this to the media in order to warn others of the risk with such a product.
Such legal complications, along with a long list of known security concerns, are among the reasons that Tropic Square has decided to pursue TASSIC.
Listen To This Episode:
This week for the “Bitcoin Magazine Podcast,” Christian Keroles sat down with long-time Bitcoiner and builder Douglas Bakkum. Bakkum is the CEO and cofounder of hardware wallet manufacturer Shift Crypto. He and his team have been working hard from very early on to create a hardware wallet experience that is suitable for newbies but has the most important advanced features for maximum sovereignty, safety and trustlessness.
This was a very wide-ranging conversation covering Bakkum’s history, the inspiration for Shift Crypto, the BitBox02 and all about bitcoin cold storage and custody.
The conversation got pretty technical, covering the nuances around wallet UX and new innovations around multisig. Bakkum is hopeful for the future of multisig but is also skeptical of folks embracing it too early. There are still lots of kinks that need to be ironed out, according to Bakkum, even though Bitcoin multisig has gotten immensely better.
The hacker that breached hardware wallet provider Ledger’s marketing database earlier this year has released personal data for thousands of users, prompting many to threaten the firm with a class-action lawsuit.
According to a tweet from network security firm Hudson Rock’s Alon Gal, a hacker allegedly behind the breach of personal data from hardware wallet Ledger in June has made all the information they obtained available online. This reportedly includes 1,075,382 email addresses from users subscribed to the Ledger newsletter, and 272,853 hardware wallet orders with information including email addresses, physical addresses, and phone numbers.
ALERT: Threat actor just dumped @Ledger’s database which have been circling around for the past few months.
The database contains information such as Emails, Physical Addresses, Phone numbers and more information on 272,000 Ledger buyers and Emails of 1,000,000 additional users. pic.twitter.com/Sv9cQwhuNy
— Alon Gal (Under the Breach) (@UnderTheBreach) December 20, 2020
“This leak holds major risk to the people affected by it,” said Gal. “Individuals who purchased a Ledger tend to have high net worth in cryptocurrencies and will now be subject to both cyber harassments as well as physical harassments in a larger scale than experienced before.”
In a response on Twitter, Ledger said “early signs” seemed to confirm that the released information was from the June data breach that compromised the personal data of many of its users. Following news of the hack, many Ledger users reported being targeted through phishing attempts. Some said they received convincing-looking emails asking them to download a new version of the Ledger software.
“We are continuously working with law enforcement to prosecute hackers and stop these scammers,” said Ledger. “We have taken down more than 170 phishing websites since the original breach.”
After experiencing months of reports on phishing attacks, many users were seemingly unsatisfied with Ledger’s response.
“If any lawyers want to start a class action suit, I’m sure many of us will jump on board,” said Twitter user Ryan Olah. “This has just gotten 10,000x worse now.”
I’m going to take legal action against you very soon.
— a Friendly Duck. HODL (@DuckHodl) December 20, 2020
Though someone’s tokens are most likely not in danger of being siphoned out of Ledger wallets, users could potentially compromise their own funds by falling for such phishing attempts sent to the affected emails or phone numbers. Many have reported that such attacks have been trying to trick them into giving up their seed phrases, prompting Ledger to reiterate:
“Never share the 24 words of your recovery phrase with anyone, even if they are pretending to be a representative of Ledger. Ledger will never ask you for them. Ledger will never contact you via text messages or phone call.”
However, some Ledger users pointed out that phishing attacks are just one possible threat they may face now that their physical addresses are public. People with a large amount of crypto holdings run the risk of being kidnapped and held until they give up their tokens, as was the case with Singaporean entrepreneur Mark Cheng in January.
“This is a serious breach and I am concerned that people now have our addresses,” said Twitter user Paul Smith. “What’s stopping them from knocking on our doors? Saying sorry, frankly, isn’t enough.”