Coinspect Security

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Coinspect Security

Coinspect Security

@coinspect

You Build. We Defend. Since 2014 protecting critical decentralized systems: L1 nodes, smart contracts audits, wallets, web3 dApps, exchanges, bridges.

Katılım July 2014
792 Takip Edilen3.1K Takipçiler

2026 Yıllık Özeti

@coinspect hesabının Twitter yılını gör

Coinspect Security retweetledi
Juliano Rizzo
Juliano Rizzo@julianor·
Now that weak entropy is a hot topic, a few tips from our experience with quick AI reviews of crypto codebases. Hopefully this helps reduce FUD and false positive/negatives in the coming days. Finding a broken RNG in a codebase does not mean it was used to generate private keys, recovery phrases, or nonces. Wallets often support dozens of chains and depend on a large number of chain-specific packages. Some dependencies may include insecure PRNG, but the wallet may never use that code path for seed generation. For example, one historically popular library had a broken RNG that was, and may still be, used by applications including wallets. But in many cases it is used to generate encryption salts or IVs, not keys. That can still be a security problem but it is not automatically a critical, remotely exploitable wallet-draining vulnerability. Those are common sources of false positives. False negatives: You need to inspect the application’s history, not only its current version. This is possible with open-source repositories, although it may require linking multiple repos to determine what code was actually shipped. For closed-source applications, reconstructing that history is harder or impossible without access to private archives. AI can help identify suspicious code quickly. Determining whether it was reachable, shipped to users, used for key generation, and practically exploitable still requires careful analysis.
Juliano Rizzo@julianor

To all the internet Batmans discovering that AI can scan public repositories for entropy flaws: we have also done this with closed-source mobile apps. The hard part is not generating findings. Most are noise. The real work is validating the few genuine issues, getting vendors to engage, assessing exposure, and building a responsible response plan. That takes far more than a tweet about saving the world.

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D'CENT Wallet
D'CENT Wallet@DCENTWALLETS·
D'CENT is not affected by the recent Coldcard incident. With many of you asking how hardware wallets generate and protect private keys, here's how D'CENT works. 👇 1️⃣ Every private key is generated inside a certified Secure Element (EAL5+/6+) using its built-in hardware TRNG (true random number generator) — not software-based randomness, and never from your phone or a server. Fully offline. 2️⃣ Full 256-bit entropy — the standard BIP39 process, with no extra mixing. Keys can't be guessed or brute-forced. 3️⃣ Keys never leave the chip. Transactions are signed inside the Secure Element, and you verify the recipient, amount, and network on the device's own screen before you approve. 4️⃣ Firmware: our Biometric Wallet has completed an independent third-party security audit (Coinspect). Generation, storage, and signing all stay inside dedicated secure hardware — the foundation of D'CENT's security. Full article detail: store.dcentwallet.com/blogs/post/how… Your keys, your control.
D'CENT Wallet tweet media
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Sunny 🦹🏻‍♂️
Sunny 🦹🏻‍♂️@SunnyPunkNoir·
@coinspect I reproduced the attack and my address set holds 2800+ BTC combined on 28th July. Right before the attack started.
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Coinspect Security
Coinspect Security@coinspect·
During the weekend we kept testing variants of the COLDCARD generator and alternative paths from each seed. Our numbers and address sets still do not match public blockchain analysis reports. If your team has reproduced the attack, please reach out so we can compare findings and understand what we may be missing. Attributing all these movements to one vulnerability without strong evidence is risky. Other exploits could be hiding in the noise.
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Anton
Anton@pepeepep42·
@coinspect I reproduced it too. Happy to compare address sets and assumptions privately if that helps.
Anton tweet media
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Rob Hamilton
Rob Hamilton@Rob1Ham·
I have spent over $10,000 scanning 100+ bitcoin ecosystem related libraries looking for vulnerabilities with Kimi K3 running as quarterback. Myself and a small "Red Team" have found multiple serious vulnerabilities impacting the ecosystem. They vary in scope severity, but this is a call to action. For any critical tier vulnerability that was identified if I was able to immediately demonstrate a POC (proof of concept), I have already responsibly disclosed to the maintainers. HERE IS HOW YOU CAN HELP ME IF YOU ARE NOT TECHNICAL: - please share with me any repository that is on github that I can scan, we want to cast a wide net. It takes a few moments for you to link github accounts, we'll take it from there - if that project does not have a SECURITY.md make an issue asking the dev to list one IF YOU ARE TECHNICAL: - If you are a maintainer or contributor to a project, I may have already scanned your repo, hit me up I'll share the results, if not I'll add your project to the list. - If I can trust you to do larger review to start looking through this stuff to give me more eyes let me know. AI Has forever changed software development. Tomorrow marks 1 week of Kimi k3 being live in open weights. We are going to accelerate.
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Jeff Schvey
Jeff Schvey@jeff_schvey·
@intangiblecoins I'm surprised we haven't heard about any white hats working to secure vulnerable funds and sweep them into safe accounts. Seems like a lot of people have been able to reproduce the attack.
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Alex Thorn
Alex Thorn@intangiblecoins·
🚨 LIKELY 4TH ORGANIZED WAVE COLDCARD ATTACK OCCURRING RIGHT NOW THERE ARE STILL SIMILAR TXS IN THE MEMPOOL WAITING TO BE CONFIRMED AND THE PREVIOUSLY-CONFIRMED TXS SIGNAL RBF OPT-IN, CHECK YOUR FUNDS AND YOU MAY BE ABLE TO RBF YOUR WAY OUT OF THIS pattern identified: blocks 960,778 - 960,792 (last ~2.5 hours, still going): • 218 transactions, 462 victim addresses, 216 fresh destinations. • 388.92748828 BTC • EVERY one has ZERO inputs predating the Coldcard firmware boundary • Rate 13.8 sweeps/block vs 0.3/block in a pre-incident control window = ~45x elevated • Topology is 1:1 — one fresh destination per victim, only ONE destination received two sweeps. No collector funnel. • Some funds have already been swept into 2nd hop addresses. these are LIKELY Coldcard victims -- they match the shape of coldcard vulnerable utxos and the elevated transaction pattern gives me high confidence they are another wave of attacks MOVE YOUR FUNDS OFF COLDCARD DEVICES ASAP AND USE HIGH TX FEES more details to come as this takes shape
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Franco 🌍🦔⚡
Franco 🌍🦔⚡@franamati·
@PabloSabbatella Coincido, en este hilo parece haber una forma, pero luego el mismo que la dijo afirma que no es segura: x.com/franamati/stat…
Franco 🌍🦔⚡@franamati

@dubdam Gracias. Nadie te dieron solución porque no hay. Actualizar la wallet (no el firmware sino nueva seed) haría que empezaran los robos. Lo más sensato es lo de "robarlas" para asegurarlas y luego devolverlas, basándose en esto, pero hay daño colateral: x.com/brian_trollz/s…

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Franco 🌍🦔⚡
Franco 🌍🦔⚡@franamati·
De lo que pasó con COLDCARD me intriga qué hubiese pasado si el bug era encontrado por los propios desarrolladores, o por un tercero que reporta de forma ética y segura. Corregir el código público o solicitar que los usuarios se actualicen y muevan fondos deja todo en evidencia.
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Coinspect Security
Coinspect Security@coinspect·
Attackers do not try every path from weak entropy to blockchain address at once. We found one variation not drained yet, identified a few users through blockchain clues, and notified them. Small next to what was stolen, but for a few users, we got there before the attackers.
Coinspect Security@coinspect

Our COLDCARD seed scan has so far found only empty or already-drained wallets. Good news: there is evidence that some affected Ethereum users moved funds to safety. Spread awareness. Every user reached now has a chance to migrate before attackers expand their search.

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Coinspect Security retweetledi
Shanaka Anslem Perera ⚡
36 days before Coldcard's seed bug was disclosed, a security firm published the instruction that would have prevented it. Coinspect wrote on 24th June 2026 that developers should avoid unnecessary wrappers around randomness generation because they can introduce unexpected fallbacks, and that randomness failures should be treated as fatal, with wallet creation stopping rather than falling back to non-cryptographic randomness. Coldcard's seed generation crossed a wrapper into another library, hit a guard that checked whether the hardware randomness flag existed rather than whether it was switched on, did not stop, and fell back to a software generator. The wrapper, the fallback, and the failure to stop. All three were named in advance. There is a second date that matters more. On 10th July, twenty days before Coldcard, the same firm disclosed a separate weak-seed flaw called Ill Bloom, with more than five million dollars already stolen from older mobile and browser-extension wallets. Coinspect said it had identified five vulnerable wallet implementations, that it was not naming them publicly, and that there were likely others it had not found. That was three weeks ago. Those five are still out there. So this is not a new risk category discovering itself. It is the sixth documented round of the same failure. Browser wallets made between 2011 and 2015 were caught by Randstorm. Android wallets rotated keys after a 2013 defect. Trust Wallet shipped a generator crackable in under a day. Libbitcoin Explorer produced Milk Sad in 2023, where researchers found more than 2,600 wallets born inside a weak keyspace and traced roughly 900,000 dollars of theft to it. Then Ill Bloom. Then Coldcard. Two things need correcting in how this is being retold. Milk Sad's 2,600 figure was wallets found to have been created from the weak keyspace, not 2,600 people drained. And it is not true that nobody built independent entropy into a product. Coldcard shipped dice input and passphrase support for years, and its manual described dice-only generation as the method that removes trust in the device. The protection existed. It was not the default, and the default is what most people press. The industry also had standards. NIST published entropy source validation, min-entropy estimation and health testing in 2018. None of it was missing. What was missing is narrower and harder. Every one of these products could prove the safe code existed. None could prove the seed generation call actually reached it in the shipped binary. Coinkite's own postmortem says earlier review confirmed the intended generator was present, not that generation reached it through the compiled dependency path. That gap has now cost money six times in thirteen years, and the last two happened three weeks apart. Bitcoin can prove a binary matches its source, a signature matches a key, and a balance matches a ledger. It still has no way to prove a key was born unguessable, and the firm that warned about it in June says five more wallets are carrying the same defect right now.
Shanaka Anslem Perera ⚡ tweet media
Shanaka Anslem Perera ⚡@shanaka86

Coldcard's own manual describes the default way of making a seed as the method that "involves the most trust." It also calls that method "low risk to users." The company's tagline is “Don't Trust, Verify”. Galaxy Research has now linked 1,367 bitcoin taken from 4,585 source addresses to a bug in exactly that path. The documentation was honest. Almost not a single person read that far. Coldcard offers three ways to create a seed. Use the device's own random number generators, which the manual says involves the most trust. Combine the device with dice, called the middle ground. Or use dice only, which the manual says "can remove all trust in the COLDCARD's hardware." So the escape hatch existed and was written down. It was simply not the default, and the default is what most people press. The deeper fracture is in one word the manual uses for both. Dice-only generation is described as fully reproducible, and that is presented as a virtue, because you can check the arithmetic yourself. The device-generated method is described as not reproducible. For firmware, reproducible is the highest compliment. Anyone can rebuild it and compare hashes. For a secret, reproducible is fatal. Anyone can rebuild it and take your coins. Same property. Opposite requirement. Everything Coldcard let you verify sat on the firmware side of that line. The verification model then breaks on its own terms. A reproducible build proves the binary matches the published source. It cannot prove the source is sound. Anyone who rebuilt this firmware would have gotten a perfectly matching hash and a broken random number generator, because the defect was in the source everyone was reproducing. Then the words appear and the evidence disappears. A weak seed and a strong seed are both 24 valid words. Both pass the checksum. Both restore a wallet. Both sit in steel for a decade looking identical. Entropy is not a property of the seed you can hold. It is a property of the invisible set the seed came from, and that set leaves no trace in the output. You can certainly prove you possess the words. The words cannot prove how unpredictably they were born. Galaxy says the median drained address had sat untouched for around three and a half years, and that the profile looks like individual self-custody rather than institutions. Those numbers are preliminary and pattern-based, and source addresses are not the same as people. But the shape is clear enough. The people hit hardest were the ones who bought the paranoid device, generated offline, checked addresses on the screen, and then never touched it again. Bitcoin replaced institutional trust with verification. Coldcard published the exact place where that substitution stops, and it was the first step of all of them. The industry can prove who holds a key. It still cannot prove where a key came from.

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Coinspect Security
Coinspect Security@coinspect·
We are reproducing the vulnerable seed-generation process. Important defensive work. Lawful recovery using private keys may sound ideal but once a private key is compromised, control of it no longer proves legitimate ownership. Without clear safe-harbor and ownership-verification procedures is risky. The safest response is to amplify the official advisory and reach users before attackers do.
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Joe Carlasare
Joe Carlasare@JoeCarlasare·
Another devastating attack on a Mk.4. Brutal
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Coinspect Security
Coinspect Security@coinspect·
On July 31, some users moved funds from long-dormant wallets into vulnerable COLDCARD generated wallets, likely without knowing the destination seed's origin. If you are migrating funds, make sure the destination wallet is not one generated previously on a vulnerable device.
Coinspect Security@coinspect

Our COLDCARD seed scan has so far found only empty or already-drained wallets. Good news: there is evidence that some affected Ethereum users moved funds to safety. Spread awareness. Every user reached now has a chance to migrate before attackers expand their search.

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Kelbie | Sovran
Kelbie | Sovran@KevinKelbie·
Could we calculate the size of this attackers GPU farm?
Kelbie | Sovran tweet media
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Coinspect Security
Coinspect Security@coinspect·
Our COLDCARD seed scan has so far found only empty or already-drained wallets. Good news: there is evidence that some affected Ethereum users moved funds to safety. Spread awareness. Every user reached now has a chance to migrate before attackers expand their search.
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Talip
Talip@otaliptus·
Ok some here are thoughts over Mk4 security bits because I'm tired at this point, here's what I think from best to worse. Keep in mind that I am assuming UID is unknown for an attacker behind a computer. This is mostly brainstorming and randomly typing on the spot, and I might be killing technical terminology or something else. I am not a hardware/embedded engineer. But these are the best "explanations" I could come up with. --- You already have 32-bit SE reseed health. Then, in theory, the fallback pad is 32 bits: UID[x, y] xor SysTick Normally, in theory, 32 SE + 32 pad gives you 64 bit static-RTC maximum. RTC is ~24 bits: 86400 * 256. If you combine these, you get, **in theory**, 88-bits. But life isn't theory, eh Pad is not entirely 32-bit secret, because a) Mk4 SysTick has 15000 practical positions, not 120000, I think, unless I'm understanding it wrong (#L72" target="_blank" rel="nofollow noopener">github.com/Coldcard/firmw…) b) UID contribution is only wafer X/Y coordinates, not full 96-bit UID well the wafer is something physical. the largest ordinary wafer is about 300mm for stm32 (only alternative that I found is 200mm but ignore for now), and on mk4 the relevant die dimension is about 5.3 mm (STM32L4S5ZIY6TR) (thx GPT 5.6 Pro for checking all docs) 300 / 5.3mm -> 56.6 -> 57 die pitches, accross a wafer. (300 is a rough physical model for now, but you get the idea) to make things easier, let's say then there are about 64 coordinate positions per axis. Then the distinct pad bit becomes (it's not multiplication, remember, it's xor) around 1-2 million. Which is, 20 - 21 bits. Therefore, we end up at 2^53 bits with SE + pad. So, this static-RTC maximum is 53 bits-ish. Is it certain? No, but I'm just brainstorming, once again. If RTC is not broken, then we get another 24 bits over this. Which makes it 77 bits. ---- With proper RTC, we're around 77 to 88 bits. Let's make it 75 if you're super pessmist, idk. Here's the question: On MK3, after Cold Boot, RTC is broken - instead of 24 bits (or similar), you get 0 bits from there. On MK4, is RTC also problematic? We don't know. At least I don't. Initial clankering and reading didn't point it out, but if it is problematic, then we have around 52 - 63 bits, which is a bit more of a problem. -------- can any of the assumptions above be wrong? maybe, most likely some details definitely. milimeters, wafer count, actual dimensions, idk. or work factor and etc. or not all 24 bits are actually 24-bits, just a register space ceiling, idk. but that's the general picture and some things I couldn't get any answer from any people, so here's my retarded opinion. sorry for all losses so far, and wishing the best to everyone 🫂
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Coinspect Security
Coinspect Security@coinspect·
@beacon302 Looks like you implemented it from the identified RNG without checking the actual device implementation.
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beac
beac@beacon302·
Coldcard RNG exploit 🚨 github.com/DK27ss/ColdCar… Root cause : rng_get() linked to MicroPython software PRNG instead of the hardware TRNG -> Mk3 seeds had ~2^40 effective states, not 2^256. ~2^40, PoC recovering mnemonic from address in ~109s.
beac tweet mediabeac tweet media
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Coinspect Security
Coinspect Security@coinspect·
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Coinspect Security
Coinspect Security@coinspect·
We adapted our Ill Bloom search code to reproduce the COLDCARD vulnerability and identified additional attacker collector addresses that do not appear in public reports. Excellent on-chain analysis by @glxyresearch also surfaced more addresses.
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