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The original response about these type of issues [1] rubs me the wrong way In particular this statement: > That being said, we were surprised by Ledger’s anno

by Ardren 7y ago

The original response about these type of issues [1] rubs me the wrong way In particular this statement: > That being said, we were surprised by Ledger’s announcement of this issue, especially after being explicitly asked by Ledger not to publicize the issue, due to possible implications for the whole microchip industry, beyond hardware wallets, such as the medical and automotive industries. As I understand they are using a standard STM32 chip for these wallets, and relying on it's basic protection. Companies make real processes designed for securely storing data, why aren't they using them? Instead they are suggesting that there is no alternative and everyone is vulnerable to this style of attack. Edit: I missed some of the backstory. They don't mention that option as their competitor (who found the security issues) already uses a secure element, like a sane person. [1] - https://blog.trezor.io/our-response-to-ledgers-mitbitcoinexpo-findings-194f1b0a97d4 https://blog.trezor.io/our-response-to-ledgers-mitbitcoinexp...

mistahenry 7y ago
To me, this is full admission of a complete lack of security competency. Building a hardware wallet without using a smart card or some other secure element that at least has mitigation’s against voltage/clock glitching, detects light, reduces the ability to measure power consumption, etc is negligent. Either they don’t know how to design secure solutions or they wanted to use cheaper chips since tamper resistant chips cost more. Neither is a good look
- logicallee 7y ago
  As most on HN know, if anyone has physical access it's game over - so when I read "critical flaw" in the title to me that meant remote key extraction (or similar remote flaw), and since there's nothing remote about this I consider it a clickbait article. No, what has been written up is not "critical". physical in-person key extraction after literally opening up a piece of hardware and glitching its exposed innards isn't a "critical flaw". it's baseline expectation. I would rate the issue raised in the article as "not a bug, won't-fix." with the explanation that "Physical key extraction will always be possible regardless of anything we do." or are people here claiming that their "better" competitors (who are using "better" hardware, more "correctly") are immune from physical attacks? EDIT: I am keeping this even if it gets voted to -4. I don't believe a physical, local (in person) glitching attack on the innards of a device, which requires physical access and opening it, constitutes a "critical" vulnerability on a hardware cryptographic device.
  - mistahenry 7y ago
    IMO there's a huge difference between invasive and non-invasive attacks. I would expect something that bills itself as "The safe place for your coins" to require a bit more effort, know-how, and tools to read out my keys than "a couple hundred dollars of equipment" and a python program. > if anyone has physical access it's game over It's actually not when you use a series of common defenses that wipe the chip when tampering is detected. Of course it's still possible to determine the private keys via perfectly executed microprobing...but there's a huge difference here. Invasive attacks require significant time in very expensive laboratories per attack, which very well may fail. Let's say managed to steal my wallet which leverages a secure element with tampering protection. If you're unaware that voltage/clock glitching will wipe the device, you may try and then you've lost. But let's say you're aware so you want to go the microprobing route. Do you have the necessary lasers and acids to get directly to the circuitry you want to read out without accidentally compromising the integrity of the top-layer sensor meshes? Do you possess a focused ion beam station (only costs ~500k USD)? By using this mesh I've made the extraction significantly more tedious and requiring far higher levels of precision for you. You've got my smart card, but I wouldn't call it "Game Over" by any means. Maybe in this amount of time I figured out that my wallet is missing. This attack here on the Tresor, though, requires physical access but can be automated. Here, physical access really is game over. I would rate this issue as "Trezor shows themselves to be an inferior solution, will not use to store my keys" Read here if you want to see more on techniques for readout and known countermeasures. https://www.cl.cam.ac.uk/~mgk25/sc99-tamper.pdf https://www.cl.cam.ac.uk/~mgk25/sc99-tamper.pdf
    - literallycancer 7y ago
      Inferior to what? The only other hardware wallet with large market share? Have a look at this: https://saleemrashid.com/2018/03/20/breaking-ledger-security-model/ https://saleemrashid.com/2018/03/20/breaking-ledger-security...
    - logicallee 7y ago
      Interesting comment, thanks. What would you say about my other question: how good are tamper evident seals - for example would a tamper evident seal on the enclosure show visually whether it has been opened (for example to exploit the flaw this article is about), or are tamper evident seals easy to get around or re-apply undetected?

by Ardren 7y ago

mistahenry 7y ago

To me, this is full admission of a complete lack of security competency. Building a hardware wallet without using a smart card or some other secure element that at least has mitigation’s against voltage/clock glitching, detects light, reduces the ability to measure power consumption, etc is negligent. Either they don’t know how to design secure solutions or they wanted to use cheaper chips since tamper resistant chips cost more. Neither is a good look

logicallee 7y ago
As most on HN know, if anyone has physical access it's game over - so when I read "critical flaw" in the title to me that meant remote key extraction (or similar remote flaw), and since there's nothing remote about this I consider it a clickbait article. No, what has been written up is not "critical". physical in-person key extraction after literally opening up a piece of hardware and glitching its exposed innards isn't a "critical flaw". it's baseline expectation. I would rate the issue raised in the article as "not a bug, won't-fix." with the explanation that "Physical key extraction will always be possible regardless of anything we do." or are people here claiming that their "better" competitors (who are using "better" hardware, more "correctly") are immune from physical attacks? EDIT: I am keeping this even if it gets voted to -4. I don't believe a physical, local (in person) glitching attack on the innards of a device, which requires physical access and opening it, constitutes a "critical" vulnerability on a hardware cryptographic device.
- mistahenry 7y ago
  IMO there's a huge difference between invasive and non-invasive attacks. I would expect something that bills itself as "The safe place for your coins" to require a bit more effort, know-how, and tools to read out my keys than "a couple hundred dollars of equipment" and a python program. > if anyone has physical access it's game over It's actually not when you use a series of common defenses that wipe the chip when tampering is detected. Of course it's still possible to determine the private keys via perfectly executed microprobing...but there's a huge difference here. Invasive attacks require significant time in very expensive laboratories per attack, which very well may fail. Let's say managed to steal my wallet which leverages a secure element with tampering protection. If you're unaware that voltage/clock glitching will wipe the device, you may try and then you've lost. But let's say you're aware so you want to go the microprobing route. Do you have the necessary lasers and acids to get directly to the circuitry you want to read out without accidentally compromising the integrity of the top-layer sensor meshes? Do you possess a focused ion beam station (only costs ~500k USD)? By using this mesh I've made the extraction significantly more tedious and requiring far higher levels of precision for you. You've got my smart card, but I wouldn't call it "Game Over" by any means. Maybe in this amount of time I figured out that my wallet is missing. This attack here on the Tresor, though, requires physical access but can be automated. Here, physical access really is game over. I would rate this issue as "Trezor shows themselves to be an inferior solution, will not use to store my keys" Read here if you want to see more on techniques for readout and known countermeasures. https://www.cl.cam.ac.uk/~mgk25/sc99-tamper.pdf https://www.cl.cam.ac.uk/~mgk25/sc99-tamper.pdf
  - literallycancer 7y ago
    Inferior to what? The only other hardware wallet with large market share? Have a look at this: https://saleemrashid.com/2018/03/20/breaking-ledger-security-model/ https://saleemrashid.com/2018/03/20/breaking-ledger-security...
  - logicallee 7y ago
    Interesting comment, thanks. What would you say about my other question: how good are tamper evident seals - for example would a tamper evident seal on the enclosure show visually whether it has been opened (for example to exploit the flaw this article is about), or are tamper evident seals easy to get around or re-apply undetected?