Bitcoin Magazine

Coinkite’s Coldcard Bug Exposed Single-Sig Risk. Multi-Vendor Multisig Is the New Bitcoin Custody Baseline

In the wake of Coldcard’s catastrophic entropy bug, self-custody advocates and experts have begun recommending a new standard, multi-vendor multisignature wallets, an approach that looks to minimize —among other threats— dependency on any single hardware wallet manufacturer.

The Coldcard entropy bug that went undiscovered since at least 2021 has taught a hard lesson to the Bitcoin self-custody advocates and users. No matter how legitimate or competent a wallet provider might seem, how well recommended and reputable, a major bug may be possible. As a result, Bitcoiners are questioning old recommendations and assumptions, including many declaring the ‘death of single sig’ the popular self-custody method of trusting the private key pair generation to one wallet alone. 

The Threat Model

Self-custody by any measure is an advanced practice in Bitcoin. Advocates recommend it as a way to protect user funds from exchange malfeasance like that seen in the cases of FTX and MtGox, among many others. But recent events have driven a revaluation of custody practices, with many bitcoin owners moving coins to exchanges — at least temporarily — while others upgrading or changing their self-custody setups altogether. Nick Neuman, CEO of Casa, claimed that 233k bitcoins moved to safety in reaction to the Coldcard hack.

To understand when self-custody makes sense and for whom, it is essential to understand your personal threat model. A threat model is the careful analysis of threats to an individual, for the purpose of designing security practices and structures ahead of time. 

A simple threat model practice can be to take a step back and think about all the possible things that worry you about self-custody, and add them to a list. Then think about all the things that advocates caution users about, and append them to that same list. Next, sort or rate items on that list based on which are most likely to happen to you, and which are most likely to happen in general. Finally, you can rank each item in the list by how catastrophic it would be if it occurred; can your current setup and plans survive the realization of that threat? 

Two of the most likely causes of loss of funds in Bitcoin self-custody are user error related to backups or forgotten passwords, and of course theft. Many of the wallets believed to be lost bitcoins that have not moved come from bad backups of private keys in the early days, resulting in data loss after a computer failed. Others simply used passwords too difficult to brute force, and then forgot them, encrypting their private keys forever.

On the theft dimension, bad entropy attacks likely rank among the most successful attacks on self-custody to date, with Coldcard joining a significant list of other wallets that have suffered bugs of the sort, intentional or otherwise, such as Trust Wallet, and many lesser-known and possibly malicious mobile wallets. In some cases, fake wallets like the iOS Sparrow Wallets simply stole user funds by keeping a copy of the user-generated private keys and sweeping the funds once deposited. In all of these examples, more thoughtful user behavior before trusting random software with your life savings is the solution. 

Once users have a clear threat model in place and a good enough understanding of the technology, designing security practices becomes more a science than an art. And while every individual has specific circumstances they need to take into account, some structures have emerged as the most resilient to most threats. One such practice becoming widely recommended and adopted among long-term self-custody Bitcoin holders is a carefully formed multisig setup. 

Multi-vendor Multisig

The term “Multi-vendor Multisig” is relatively new in the self-custody niche. The term “multisig” has nevertheless gone viral in 2026, clearly triggered by the Coldcard hack that saw the loss of over 100 million dollars worth of bitcoin, mostly from single seed wallets. Most single-seed Coldcard users appear to have generated their private keys on the device without adding an extra passphrase, extra words that add custom entropy to the private keys, nor without extra dice rolls, which do the same in a different format. 

The weak entropy from the Coldcard firmware — which users had no reason to distrust, given the company’s strong brand — in turn made guessing the related private keys easy, with a bit of custom work, which hackers eventually figured out. 

The resulting viral interest in multisig is warranted. Multisig Bitcoin wallets protect users from such hardware manufacturer errors by letting users construct a Bitcoin address that requires signing from multiple private keys and thus multiple devices, in what is known as a Bitcoin script.

Bitcoin scripts are contracts of sorts that set spending conditions for a bitcoin wallet. All Bitcoin wallets can be thought of as having some kind of script involved, with the simplest and most popular being that anyone who can sign a valid transaction can spend all or any funds therein. Multisig scripts instead require a threshold of valid signatures from different keypairs to result in a valid withdrawal. These scripts are enforced by the Bitcoin consensus rules.

Multi-vendor multisig theory posits that users should make sure every keypair used to construct a Bitcoin multisig is generated from a different wallet vendor. 

One example that is likely popular today might be the use of a Trezor Safe 7 hardware wallet with one key, a second key generated by a Ledger Nano, and a third key generated by a multisig wallet provider, considered a recovery key. A script of this sort would require any 2 valid signatures out of the three possible signatures in the setup.

By using two different hardware wallet providers, the user minimizes trust in any single wallet vendor, protecting them from an entropy failure like the one seen in Coldcard. 

Other Multisig setups can add more keys, with a 3-of-5 threshold also being common and a standard offering of a multisig-specialized wallet like Casa. It is at this point that the terminology commonly used and understood to describe Bitcoin spending software starts to break down, and as a result merits clarification.

Wallets like Casa are software interfaces that let users combine partially signed transactions from different private key pairs. In this scenario, it becomes more useful to describe ‘hardware wallets’ like Trezor or Ledger as ‘key signers’ since no single keypair in the set holds enough of the key material to spend all the Bitcoin held in the Multisig script address. 

So Casa is a Multisig wallet that lets you use a threshold of hardware signers to secure and send bitcoin funds. Fundamentally, they help users interact with Bitcoin script and create consensus-valid transactions easily. Other examples of such multisig wallet providers include Nunchuck, Sparrow desktop wallet and Unchained Capital. 

In cases like Casa and Unchained, the wallet provider offers users a recovery key controlled by the company, which some users find useful. Nunchuck and Sparrow, on the other hand, are designed for full user autonomy in this regard, though Nunchuck does offer a premium recovery key-related plan as well. 

The Upsides of Multivendor Multisig

Another benefit of a multisig wallet is its potential resistance to the infamous wrench attacks. Countries like France, which make Bitcoin and crypto ownership a matter of public record as a consequence of tax filings, have become focal points for crypto theft-related kidnapping. Self-custody or not, targets of this kind of crime are vulnerable to theft, particularly when the funds can be moved in full quickly, be it from a custodial exchange the user can access from their phone, or some self-custody setup.

Advanced forms of multisig, like multi-jurisdictional or time-locked multisig, make it so that users have to travel, ideally through an airport, in order to reach other key signers needed to construct a valid bitcoin transaction. Or perhaps the recovery key involved in the multisig has the condition that it will not sign for two weeks after the user submits the request and corresponding transaction data. The result is the removal of the final central point of failure in Bitcoin custody: the user’s own willingness to send the bitcoin, particularly when under duress.

While best practices in the case of wrench attacks broadly try to avoid ending up in that situation in the first place, making it difficult to spend your coins actually protects users from a wide range of attacks as well, including phishing schemes and other forms of social engineering that use pressure tactics to fool users into sending funds quickly. 

Multisig has also begun to enable novel forms of Bitcoin insurance, as demonstrated by AnchorWatch, a multisig wallet and insurance company that offers bitcoin theft protection denominated in BTC. The company’s services today are primarily offered to Americans through the Lloyd’s of London insurer. 

The Downsides of Multisig

One critical downside of Multisig is that the user does not only need to have access to the threshold key material needed to sign, be it two hardware wallets as in our example, or one of the hardware wallets and a recovery key from the wallet company. The user also needs to store a copy of the Multisig script or template, so that they can recreate the smart contract and thus the valid withdrawal conditions for spending. Most Multisig wallets store this information for clients, but they will also send a copy to users so they can recover independently of the Multisig wallet, should it one day go offline. 

This post Coinkite’s Coldcard Bug Exposed Single-Sig Risk. Multi-Vendor Multisig Is the New Bitcoin Custody Baseline first appeared on Bitcoin Magazine and is written by Juan Galt.

Bitcoin Magazine

Chinese AI Beats Restricted OpenAI and Anthropic Cybersecurity Models, Bitcoin Industry Warns

Bitcoin company leaders and open-source developers are publicly stating that Chinese AI models are currently outperforming restricted American frontier systems in defensive cybersecurity work, forcing researchers to rely on them to secure critical Bitcoin infrastructure.

Rob Hamilton, CEO of AnchorWatch, a Bitcoin self-custody insurance company, reported cripling American AI restrictions. After integrating OpenAI’s trusted cyber program (having already completed KYC months earlier), he was blocked from further analysis on a codebase he had already responsibly disclosed. “It absolutely guts me as a patriotic American to have to do this, but I will be going back to using Chinese open source models to conduct my research to protect Bitcoin infrastructure,” Hamilton wrote. “Black hats will not hit these issues. The white hats will.” Days later, he gained access to OpenAI’s “Daybreak Blue” cyber model and was blocked again within 19 minutes while red-teaming Bitcoin infrastructure.

Francis Pouliot, founder of Bull Bitcoin, a Bitcoin-only exchange focused on self-custody infrastructure, described the situation bluntly. “I have never seen OpenAI this cucked. It’s cucked beyond belief now. Not even for security, for anything related to Bitcoin,” he posted. “USA AI industry is completely cooked if they don’t change this path,” he concluded, adding “Open-source Chinese LLMs. [orange heart emoji],” meaning that open Chinese models like Kimi K3 are actually helpful to Bitcoin. In a follow-up, Pouliot detailed how a Chinese open-source model identified a money-stealing exploit in a project he was auditing, demonstrated it on regtest, and helped patch it. When he asked the American models he pays for to review the same patch, they refused.

PortlandHODL, a Bitcoin Core contributor who builds for AnchorWatch, publicly highlighted the performance gap. “US-based Frontier AI Model – ‘You’re absolutely right!’ Chinese Open Model – ‘78 critical vulnerabilities found.’ The implications of this are unfathomable,” he posted. In a follow-up, he added that he felt he was “basically asking Xi to not get my software hacked at this point,” calling for OpenAI and Anthropic to create proper access programs for U.S. citizens doing defensive security work.

Alex Thorn, Head of Firmwide Research at Galaxy, signed a recent Bitcoin Policy Institute open letter demanding trusted access to frontier models for open-source defenders. “Americans should not have to rely on Chinese AI to defend themselves, their projects, companies, or clients from cyber-attacks,” he wrote. “RED TEAM NEEDS THE MODELS.”

On August 10, the Bitcoin Policy Institute — a Bitcoin and, of late, AI-focused policy think tank — published an open letter signed by more than 70 organizations across the digital-asset ecosystem, including major custodians, exchanges, mining firms, and open-source development groups. The letter calls on frontier AI labs to establish clear trusted-access programs for qualified open-source and digital-asset defenders. It argues that current restrictions and safety guardrails leave legitimate security researchers without access to the strongest models, forcing them to rely on less capable open-weight alternatives while sophisticated attackers face no such limits. The signatories request early access to cyber-capable models, sufficient compute, secure environments for reviewing code, and direct channels with lab security teams, stating that frontier AI could become one of the most powerful defensive technologies available if defenders are given fair access.

These statements reflect a broad pattern among Bitcoin security researchers: American models from OpenAI and Anthropic frequently refuse or restrict legitimate defensive work, even to users who are supposed to have been granted explicit access, while Chinese models such as Kimi K3 operate without the same guardrails and are delivering confirmed results. Concerns about hosting infrastructure of Chinese models being an attack vector can also be mitigated, since they are open source and can be run on American-hosted data centers, a trend that is likely to threaten the U.S. AI market if it continues.

Coldcard Exploit Triggers Ecosystem-Wide Response

The cybersecurity pressure became acute in the Bitcoin industry after a firmware flaw in Coldcard hardware wallets was exploited beginning July 30, resulting in the theft of well over $100 million in bitcoin from seeds generated with insufficient entropy. Bitcoin Magazine published an urgent advisory urging affected users to migrate funds: COLDCARD SECURITY RISK: IMMEDIATE ACTION REQUIRED.

In response, a volunteer effort known as the Bitcoin Red Team formed, led by open-source developer Calle (creator of Cashu and the Android version of Bitchat) and Rob Hamilton. The group has conducted large-scale AI-assisted audits of Bitcoin open-source repositories, using models including Kimi K3 as the primary workhorse alongside limited access to Western systems. Early results, covered by Bitcoin Magazine, showed thousands of findings across hundreds of projects, including dozens of critical issues, with spending covered largely by OpenSats.

By August 8, after more than 100 hours of work involving dozens of contributors, the team reported scanning 501 projects and producing 7,958 findings, of which 1,280 were rated high or critical severity. The majority of compute spend continued to go to Chinese open-weight models.

Lessons from the Red Team Campaign

Most recently, Calle shared lessons from the intensive red-team period. The effort has essentially completed a basic scan of virtually the entire Bitcoin open-source landscape; low-hanging fruit is largely exhausted, the developer wrote on this X account. Maintainers across projects have validated many of the critical and high-severity reports, while response times from projects vary widely and serve as a signal of overall health.

Key takeaways include the need for every project to maintain its own permanent AI audit pipeline going forward. Projects that began such reviews months earlier are in a markedly stronger position. Unmaintained repositories should be treated as likely broken and unreliable. 

Calle also warned that the human-only era of open-source security review is over; verification is now effectively free, and information overload must be handled with AI rather than complaints about PR slop. Multiple concurrent and diverse human approaches remain the strongest method for finding vulnerabilities, and external red-teaming will likely be required indefinitely. 

Calle also repeatedly emphasized that developers should stop writing security-critical code in C. In a follow-up post he explained: “we’re finding memory-safety vulnerabilities in c projects that are prevented by default in many other languages. In the past, finding a simple buffer overflow wasn’t enough. You’d need a highly skilled hacker to turn the vulnerability into a working end-to-end exploit. Today, that’s a single prompt.”

Bitcoin was the first major open-source ecosystem to confront this collision between accumulated human code and frontier AI capability. The rest of the software world is expected to follow.

This post Chinese AI Beats Restricted OpenAI and Anthropic Cybersecurity Models, Bitcoin Industry Warns first appeared on Bitcoin Magazine and is written by Juan Galt.

Bitcoin Magazine

Breez Announces Glow, an Open Source Bitcoin to Stablecoins Progressive Web App

Developed by Breez in partnership with Bitcoin Spark, the Glow app lets users send stablecoins from their Bitcoin balance, while empowering developers to build better user experiences without having to worry about the difficult parts of building on top of Bitcoin. Breez’s SDK takes care of asset exchange in the background while supporting lightning payments through its Spark integration. 

“Glow is a Bitcoin app for everyone,” said the company in a press release shared with Bitcoin Magazine. Users can access the app on both Apple and Android app stores. Glow re-invents the Bitcoin wallet experience, deviating from the seed phrase backup flow that many wallets attempt to introduce users to. Instead, Glow leverages the Passkey standard engineered and now encouraged by the Silicon Valley giants, which makes passwords and, in this case, pass phrases a thing of the past. Despite the change, Glow promises self-custody and cryptographic control over funds to its users, in an auditable software package. 

As an MIT-licensed, free and open source progressive web app (PWA), Glow is built so that developers can look under the hood, take it apart, and implement features as they see fit, leveraging the Breez API and SDK. Besides the Passkey login, Glow has full support for native Lightning payments, sending and receiving with customizable Lightning addresses that look like emails, such as BM@breez.tips. First deployed to a Bitcoiner user base, Glow can currently send USDT and USDC across most networks and blockchains through their partnership with Flashnet, drawing value from the user’s Bitcoin balance. 

Glow comes integrated with a couple of onramps from the start as well. Users can onboard to bitcoin instantly via Cash App and MoonPay which the SDK connects to via their API. Sats arrive in seconds. The app also has contacts integration, letting users save their friends’ lightning addresses as a contact, hiding away ugly public keys and lightning invoices and delivering a more familiar and mainstream payments app experience. 

Users can also avoid bitcoin’s volatility by swapping their BTC holdings to USD value at will and, according to the press release, they earn sats as they do. Glow’s stablecoin is USDB; the B stands for Bitcoin, a stablecoin issued by Brale Inc which is licensed as an MSB across over 45 states, and claims to be compliant with GENIUS Act standards: “Regulated & fully backed Issued by Brale, a U.S. regulated entity, and 100% backed by T-bills, cash, and cash equivalents”. There appears to be no way to verify Brale’s compliance with the GENIUS Act right now as the regulations are still being implemented and do not take effect until 2027.

What is remarkable about USDB is that it is a Bitcoin native stablecoin, deployed through the Spark protocol, which is compatible with the Lightning Network, essentially unlocking the stablecoin across Bitcoin rails. USDB holders earn up to 6% APY delivered from Flashnet DEFI exchange’s profits, according to a Spark announcement earlier this year. 

Breez believes this combination of partnerships and technologies means that “Bitcoin has finally crossed a threshold.” The UX unlocked by Glow is now fully available to developers as a software development kit, something unimaginable by traditional finance. 

This post Breez Announces Glow, an Open Source Bitcoin to Stablecoins Progressive Web App first appeared on Bitcoin Magazine and is written by Juan Galt.

Bitcoin Magazine

Bitcoin Red Team Finds 85 Critical Flaws Across 390 Open Source Repos After Coldcard Exploit

Rallied by the recent, catastrophic vulnerability in Coldcard hardware wallets, exploited to the tune of over $100 million, the Bitcoin community has rallied to prevent future critical bugs in the industry’s open source software.

PSA: Any users of Coldcard wallets that have not migrated their bitcoin to new seeds generated in secure firmware are still at risk. It may not be too late to act; see advisory on the matter. 

Led by Calle, software engineer, avid vibe coder and creator of the Android version of Bitchat, and Rob Hamilton, the CEO of Anchorwatch a Bitcoin self-custody insurance company, the Bitcoin Red Team has now secured funding, with over $40,000 spent in AI tokens to audit over 390 Open Source repositories across Bitcoin. 

Colloquially called the “Bitcoin Red Team”, with memes about Rob Hamilton and Calle now being the CEO and CTO of Bitcoin, this AI-driven security audit is having a serious impact across the industry. Just a few days ago, buried in the news of ongoing thefts of bitcoin from MK3+ Coldcards due to an RNG bug, Boltz exchange announced it would be pausing operations to catch up with AI-driven hacking attempts. 

“27.5 hours in, we’ve filed 4,962 findings across 390 projects. 85 critical and 635 high severity issues. We’re at 2.31 h+c findings per person per hour,” said Calle in the most recent update on Red Team efforts to shore up the industry’s cybersecurity.

The Red Team security review effort is using models like Kimi K3, GPT Sol, Fable, Opus and GLM5.2, some of the most expensive and cutting-edge models in the market. At first, access to OpenAI and Anthropic models was limited, leading to an over-reliance on Chinese open-source models, a fact which many in the industry lamented and saw as a bad omen for U.S. AI dominance. But as the Red Team project grew in influence since last week’s Coldcard hack, connections have been established and confirmed with OpenAI, giving Red Team access to GPT Sol. Hamilton’s mention of Fable in his August 4 tweet suggests access to Anthropic has also been established.

Expenses which were last tallied at over $40,000 have been covered by OpenSats, a non profit 501c3 organization dedicated to funding open source Bitcoin development projects. The Bitcoin Red Team does not currently have a website or a GitHub repository to link to, but the team is made up of many individuals within the Bitcoin industry. Individuals publicly thanked for their support include but are not limited to danielabrozzoni, lylepratt, stutxo, benthecarman, thesimplekid. 

Hamilton shared that a custom harness has been built and is evolving quickly. Made up at one point of 171,599 lines of code, the harness is designed to identify and test critical Bitcoin software libraries and high-load-bearing code, identify and document vulnerabilities, reproduce them and package the proven data into useful reports. Ultimately delivering the information responsibly to engineers in the industry. Hamilton also shared that Red Team intends to open source the harness such that Bitcoin companies can run it against their closed-source code. 

Red Team is actively reaching out to relevant open source projects with critical vulnerabilities discovered, leading to a broad sense of dread from engineers in the industry when they receive cold direct messages from Hamilton or Calle, as seen in various humorous screenshots shared on social media.

https://x.com/callebtc/status/2085035257477190080 

Among the key insights shared by Red Team publicly as this AI-driven security update of Bitcoin FOSS takes place, Hamilton shared that engineers with specific subject matter could sometimes yield high-value results from the Harness, which might otherwise “smell out something is wrong,” but might be missing niche context. An insight which speaks to the importance of having human intelligence and experience work hand in hand with the AI to efficiently identify critical vulnerabilities.

Hamilton also ended a multi-day Red Team effort after the Coldcard hack with some personal notes. He said that the discovered vulnerability in Coldcard random number generators and consequent exploitation of the bug by hackers had been a “spiritual attack” on Bitcoin and the self-custody ethos of the industry, “I mean that in the literal sense of the words”. After expressing grief for the losses experienced by many Bitcoiners during this now historic hack, Hamilton closed his tweet with a tone of hardened resolution:

“While things are not easy right now. I have the highest conviction ever in my life that the idea and technology of Bitcoin is worth fighting for. To that end. There is no Bitcoin without self-custody. This is non-negotiable.”

This post Bitcoin Red Team Finds 85 Critical Flaws Across 390 Open Source Repos After Coldcard Exploit first appeared on Bitcoin Magazine and is written by Juan Galt.

Bitcoin Magazine

Coinkite Releases Fixed Firmware After Coldcard Bug; AI Likely Involved In The Breach

Over a thousand bitcoins are believed to have been stolen so far in a hack that started to be discussed on social media in the afternoon of July 30th. Coinkite, one of the most reputable hardware wallet manufacturers, was revealed to have a critical bug in the way it generated secure private keys for its Bitcoin hardware wallets. Industry experts believe AI was used in the breach.

Coldcard MK3 devices with firmware version 4.0.1 (March 2021) through 4.1.9 are the worst affected. 12- or 24-word seeds generated by the device that did not include user-generated dice rolls or a BIP 39 extra passphrase are vulnerable. 

Users who fit this category, who have bitcoins in an MK3 Coldcard and did not use the dice roll feature for extra entropy or the extra passphrase, should consider themselves at risk and move their coins as soon as possible from the wallets. Bitcoin Magazine technical writer Shinobi has published a guide on the topic, and Coinkite has also published a guide and advisory. 

The vulnerability was a specific line of code in the firmware, a low-level software codebase that controls the hardware. This firmware appears to be upgradable. The Coinkite advisory was updated this morning, advising users to upgrade device firmware for all three chips, MK3, MK4 and MK5 devices, including the Coldcard Q:

“Updated July 31, 2026 at 9:33 a.m. EDT: Fixed firmware is now available. Mk4 and Mk5 users must update to version 5.6.0 or later. Q users must update to version 1.5.0Q or later. For Mk3, update to version 4.2.0 or later.”

Coinkite also explained in their advisory that updating the firmware does not mean that the private and public keys generated by the vulnerable firmware before it are now secure; those keys remain vulnerable as they were effectively created with a weak password. After the firmware is updated, a new wallet needs to be created, and the funds need to be sent onchain to the new addresses to secure the funds. Coinkite wrote:

“Updating the firmware does not change or repair an existing seed. If your seed was generated before the fixed firmware version for your model, follow the migration guidance below unless the independent dice-entropy exception applies to you.”

Some Multisignature Wallets May Be At Risk

Peter Todd, Core contributor and cybersecurity engineer, today addressed specific edge cases for multi-signature wallets that use a threshold of Coldcards to secure funds. “Example case: you have a 2-of-3, with 2 Cold Cards, and a 3rd uncompromised device. If you move your funds, the moment your script is revealed for the first time – previously hidden behind the address hash – the attacker now knows enough to use the compromised 2 cold card keys to steal your funds.”

The transaction that reveals the multisig script might be unconfirmed, giving hackers enough time to create a competing transaction with a higher fee. Fortunately, such cases have a solution: the MARA mining pool can help in this case with their private mempool mining service, Slipstream; “because they promise to keep your transaction – and thus pubkeys – secret until they’re already in a block. Dramatically reducing the ability of the attacker to steal the funds,” said Todd. He added that “If you’ve already reused addresses, this isn’t relevant, and you should just try to move your funds ASAP. But if you haven’t, MARA may be able to help.”

Beyond The Immediate Crisis

NVK, one of the co-founders of Coldcard, published a long post on X with an initial analysis beyond the basic security steps needed to secure funds. In it, he wrote that the company is “committed to working with affected users who want to pursue a police report, insurance claim, or their own investigation”, including “a written incident summary specific to your loss and any transaction data we can share”. 

Beyond the immediate crisis, NVK pointed to a broader tech shift as the hacking capabilities of AI begin to change previous cybersecurity dynamics and expectations. In the blog post he wrote: 

“To every other developer: we believe this is a sober reality of the new AI paradigm. AI-assisted code review can now find latent bugs at a speed that is outpacing even the industry’s most seasoned experts. If your firmware is open-source or has ever been public, assume it’s already being read by attackers and defenders alike.”

The hack and over 70 million dollars in estimated stolen funds in the past 24 hours are an effective bounty paid to hackers who are now likely auditing every wallet codebase available for vulnerabilities. While the Bitcoin and broader crypto industry has generally operated under the assumption that hackers will test their code, the development of AI models optimized for cybersecurity accelerates these processes. 

Industry experts gathered in a long X Spaces public call last night, discussing the topic for many hours. Beyond the immediate recommendations and answering questions to Bitcoin users throughout the long Spaces, analysis of what is likely to follow in the coming weeks was also discussed. Other wallet providers are likely to get probed, and especially open source projects which generate private key material will be tested. 

The X Spaces was not recorded, likely to preserve the privacy of everyone in the call; however, initial sentiment suggests companies will need to be auditing their code with the latest frontier models, as a matter of survival. The latest cybersecurity-oriented AI models by Anthropic, OpenAI, Moonshot’s Kimi K3 and others are already available to the public. Many companies in the Bitcoin industry already use these to test the integrity of the code, but some might not be, and the race to find vulnerabilities in wallet-facing code will certainly continue, especially in the following weeks.

Ultimately, today we grieve lost coins, and a state of introspection and careful review occurs. Beyond this now historic hack will be an open source self-custody industry and infrastructure that is likely to be orders of magnitude more secure, with very hard lessons learned. After all, every hacker with an AI agent is likely testing defenses now. 

Multi-vendor, Multi-key Wallets and Covenants

Future high sovereignty wallets, be it at the retail or corporate level, are likely to not depend on any single vendor. Multisignature wallets, when well done, can distribute vulnerability risks across different code bases, teams and hardware. 

User-generated entropy was also a major theme in the X Spaces discussed earlier, with dice roll-generated entropy brought up regularly as a solution. Coldcards, as well as other hardware wallets like Foundation Devices, guide users on how to add their own entropy properly; many dice need to be rolled, ideally north of a hundred individual rolls. Once done, however, dice rolls represent a non-software source of randomness for wallets that also separates users from the edge-case risks in software- or hardware-generated entropy.

Covenants a popular soft fork among a certain niche in the Bitcoin industry have also started to be brought up as further step to strengthen the self-custody industry. This upgrade to the Bitcoin consensus which might be hard fought if achieved at all, could give users important smart contract capabilities, such a wallet that can only send to a white list of addresses, something not possible in Bitcoin script today. 

This post Coinkite Releases Fixed Firmware After Coldcard Bug; AI Likely Involved In The Breach first appeared on Bitcoin Magazine and is written by Juan Galt.