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Thank you for that. Just to make one thing clear, the person who destroyed the contract was after people's money. He posted a list of contract addresses in the

Thank you for that. Just to make one thing clear, the person who destroyed the contract was after people's money. He posted a list of contract addresses in the github issue, most of them look like ICO wallets, with a transaction made the time before he destroyed the contract. The transaction was from him to his wallet trying to drain the wallets. After he failed to he went to the destroy function thinking it will propagate to the wallets and moving the funds to him ( this part is just a theory ) or he is just a jerk who wanted to see the world burn.

charlesdm 9y ago
Frankly, the fact whether or not it was malicious doesn't matter. The original developers fucked up, and there is no genuine excuse for that (regardless of the fact whether or not he was able to steal those funds). This probably could have been fixed with basic testing.
- vesinisa 9y ago
  This I don't understand about Ethereum. Just look at all the companies like Microsoft or Apple with millions to spare, or massive community efforts like Linux kernel, either with no shortage of means and resources to make their systems resistant to simple programming bugs. But history clearly shows that no amount of processes, audits, static analysis or eyepairs help: bugs just keep on being found where ever security folks look for them, and the harder they look, the more they find. Upside is, these systems can be patched, which is comforting as clearly there just is no bug-free code. Yet, people keep on pouring millions of dollars worth of virtual tokens to these experimental blockchain systems that are fundamentally designed so that any bug of certain class means the money is forever, irreversibly lost - as if these crypto contracts were some mythical new breed of software written by infallible Gods.
  - zanny 9y ago
    This is why Rust is so promising. The problem at Apple / MS / Linux / etc is they are massive houses built on bare foundations. Everything traces its roots back to C, and back to exploitative vulnerabilities in the code. Rust itself is not close to safe since it depends on LLVM which itself can be a source of myriad bugs related to C++. But its proving in my experience to be a much more practical foundation, and going forward there is a lot of value in that.
    - adambyrtek 9y ago
      Better languages can help to avoid certain classes of errors, but won't prevent bugs in the business logic of your code, so I'm not sure how this is relevant to contracts.
    - bpicolo 9y ago
      Has there ever once been a critical llvm vulnerability? I've seen the occasional bugs related to it, but they tend to crash the compiler rather than produce bad binaries, no?
      - tom_mellior 9y ago
        Here's a list of LLVM bugs found using Csmith: http://embed.cs.utah.edu/csmith/llvm-bugs.html http://embed.cs.utah.edu/csmith/llvm-bugs.html . Plenty of these are wrong code bugs. Security-related compiler bugs very rare, but they do exist, at least in graphics shader compilers: http://www.doc.ic.ac.uk/~afd/homepages/papers/pdfs/2017/OOPSLA.pdf http://www.doc.ic.ac.uk/~afd/homepages/papers/pdfs/2017/OOPS... . My impression is that many of these shader compilers are based on LLVM, but this is mostly conjecture. (I do recall a video game crashing on me with internal LLVM errors from the graphics driver.)
    - kornish 9y ago
      The bug in question isn't related to memory safety, overflow, or concurrency, though.
    - steveklabnik 9y ago
      We do occasionally run into bugs between Rust and C++ semantics with LLVM, but they’ve been pretty minor, and LLVM has largely fixed them, to the point of adding instrinsincs to fix these issues. Bugs happen no matter the language, even if LLVM was in Rust it would have them.
    - olliej 9y ago
      this isn't a code error -- it's a logic error. No amount of "safeness" in the language will save you from telling the language, without breaking the rules, from doing something that is "wrong". For instance: sudo rm -rf / Every part of that is completely sound and correct. There are no buffer overflows, emory corruption, or anything. You wrote a completely correct command to do something (probably) really wrong.
  - DennisP 9y ago
    The saving grace of Ethereum contracts is that they're very short. Many are under a thousand lines of code, so it's not crazy expensive to pay expert auditors to review every line. It also looks like an ideal use of formal verification techniques, and there's a lot of work going into making that practical. Plus you can keep things a lot safer by writing your contracts in the simplest, most obviously-correct way possible. The fact that you can do these things doesn't save you from people who don't. Parity's last audit happened before they made a major architectural change; if they'd gotten new audits this probably would have been caught. They also have the most complex wallet code I've seen, often dipping into assembly. It's true that you can't be completely sure of avoiding bugs, but with decent practices I think it's less of a problem on Ethereum that it is in medical equipment, airliners, and nuclear reactors.
    - mbrock 9y ago
      It's kind of like, do you think it's humanly possible to correctly encode the rules of chess in, say, 6502 assembly? You probably won't do it on the first try. And you wouldn't immediately bet a million dollar on it. But is it possible? Yes. A multisig wallet shouldn't be more complicated. Could you prove the correctness of the 6502 chess? Sure. Formal methods are not black magic. You need a semantics of the machine and a formalization of the rules. Can you make mistakes in specifying? Yeah, duh. So combine it with peer review and throw in a bug bounty and fuzzing.
      - schoen 9y ago
        Chess is a nice example in this analogy because there are rules that people are less familiar with and might well forget about or implement incorrectly. For example, the complete castling rules are not trivial, like with the king not passing through a square currently attacked by an opposing piece https://en.wikipedia.org/wiki/Castling#Requirements https://en.wikipedia.org/wiki/Castling#Requirements and some people may neglect or misimplement en passant https://en.wikipedia.org/wiki/En_passant https://en.wikipedia.org/wiki/En_passant and the rules related to repetitive situations in the end game: https://en.wikipedia.org/wiki/Threefold_repetition https://en.wikipedia.org/wiki/Threefold_repetition https://en.wikipedia.org/wiki/Fifty-move_rule https://en.wikipedia.org/wiki/Fifty-move_rule (Implementing the threefold repetition rule requires maintaining historical state of a different kind than any other chess rule!) I've seen impressive hyperminimalist chess implementations that were missing these things, but that totally felt like real chess almost all of the time.
  - trhway 9y ago
    Bugs almost always mean lost money. In block chains it is just more direct and visible.
  - AstralStorm 9y ago
    There is a way, reforming everything as an automatic math proof. Because even security is driven by capitalism sort term gains almost nobody does this. It takes time and sometimes serious math skills.
- DyslexicAtheist 9y ago
  exactly, it's a problem with tooling that could have been prevented. Good points by Matthieu Suiche here going deeper into why: https://twitter.com/msuiche/status/928238570162102273 https://twitter.com/msuiche/status/928238570162102273
tom_mellior 9y ago
> He posted a list of contract addresses in the github issue, most of them look like ICO wallets What are you talking about? Do you mean this issue: https://github.com/paritytech/parity/issues/6995 https://github.com/paritytech/parity/issues/6995 ? What list are you referring to?
arez 9y ago
Just to make one thing clear, you're just assuming. The guy clearly stated that he just tried out different things and never really intended to steal something. If you give out an API make sure that I can't break it by calling it, otherwise it's your fault not mine. The guy seemed also pretty nervous in the gitter channel, he asked if he really broke something and if he gets arrested.
shp0ngle 9y ago
He claimed he tried it, thinking it can't go through. And it seems plausible, since you he was researching similar attacks from the past. He had no reason to make the github issue afterwards, if he was a blackhat who knew what he was doing. His entire presentation doesn't seem like that. (Or even like "someone who is trying for no real reason to try to look innocent". He didn't have to be public at all.)

charlesdm 9y ago

Frankly, the fact whether or not it was malicious doesn't matter. The original developers fucked up, and there is no genuine excuse for that (regardless of the fact whether or not he was able to steal those funds). This probably could have been fixed with basic testing.

vesinisa 9y ago
This I don't understand about Ethereum. Just look at all the companies like Microsoft or Apple with millions to spare, or massive community efforts like Linux kernel, either with no shortage of means and resources to make their systems resistant to simple programming bugs. But history clearly shows that no amount of processes, audits, static analysis or eyepairs help: bugs just keep on being found where ever security folks look for them, and the harder they look, the more they find. Upside is, these systems can be patched, which is comforting as clearly there just is no bug-free code. Yet, people keep on pouring millions of dollars worth of virtual tokens to these experimental blockchain systems that are fundamentally designed so that any bug of certain class means the money is forever, irreversibly lost - as if these crypto contracts were some mythical new breed of software written by infallible Gods.
- zanny 9y ago
  This is why Rust is so promising. The problem at Apple / MS / Linux / etc is they are massive houses built on bare foundations. Everything traces its roots back to C, and back to exploitative vulnerabilities in the code. Rust itself is not close to safe since it depends on LLVM which itself can be a source of myriad bugs related to C++. But its proving in my experience to be a much more practical foundation, and going forward there is a lot of value in that.
  - adambyrtek 9y ago
    Better languages can help to avoid certain classes of errors, but won't prevent bugs in the business logic of your code, so I'm not sure how this is relevant to contracts.
  - bpicolo 9y ago
    Has there ever once been a critical llvm vulnerability? I've seen the occasional bugs related to it, but they tend to crash the compiler rather than produce bad binaries, no?
    - tom_mellior 9y ago
      Here's a list of LLVM bugs found using Csmith: http://embed.cs.utah.edu/csmith/llvm-bugs.html http://embed.cs.utah.edu/csmith/llvm-bugs.html . Plenty of these are wrong code bugs. Security-related compiler bugs very rare, but they do exist, at least in graphics shader compilers: http://www.doc.ic.ac.uk/~afd/homepages/papers/pdfs/2017/OOPSLA.pdf http://www.doc.ic.ac.uk/~afd/homepages/papers/pdfs/2017/OOPS... . My impression is that many of these shader compilers are based on LLVM, but this is mostly conjecture. (I do recall a video game crashing on me with internal LLVM errors from the graphics driver.)
  - kornish 9y ago
    The bug in question isn't related to memory safety, overflow, or concurrency, though.
  - steveklabnik 9y ago
    We do occasionally run into bugs between Rust and C++ semantics with LLVM, but they’ve been pretty minor, and LLVM has largely fixed them, to the point of adding instrinsincs to fix these issues. Bugs happen no matter the language, even if LLVM was in Rust it would have them.
  - olliej 9y ago
    this isn't a code error -- it's a logic error. No amount of "safeness" in the language will save you from telling the language, without breaking the rules, from doing something that is "wrong". For instance: sudo rm -rf / Every part of that is completely sound and correct. There are no buffer overflows, emory corruption, or anything. You wrote a completely correct command to do something (probably) really wrong.
- DennisP 9y ago
  The saving grace of Ethereum contracts is that they're very short. Many are under a thousand lines of code, so it's not crazy expensive to pay expert auditors to review every line. It also looks like an ideal use of formal verification techniques, and there's a lot of work going into making that practical. Plus you can keep things a lot safer by writing your contracts in the simplest, most obviously-correct way possible. The fact that you can do these things doesn't save you from people who don't. Parity's last audit happened before they made a major architectural change; if they'd gotten new audits this probably would have been caught. They also have the most complex wallet code I've seen, often dipping into assembly. It's true that you can't be completely sure of avoiding bugs, but with decent practices I think it's less of a problem on Ethereum that it is in medical equipment, airliners, and nuclear reactors.
  - mbrock 9y ago
    It's kind of like, do you think it's humanly possible to correctly encode the rules of chess in, say, 6502 assembly? You probably won't do it on the first try. And you wouldn't immediately bet a million dollar on it. But is it possible? Yes. A multisig wallet shouldn't be more complicated. Could you prove the correctness of the 6502 chess? Sure. Formal methods are not black magic. You need a semantics of the machine and a formalization of the rules. Can you make mistakes in specifying? Yeah, duh. So combine it with peer review and throw in a bug bounty and fuzzing.
    - schoen 9y ago
      Chess is a nice example in this analogy because there are rules that people are less familiar with and might well forget about or implement incorrectly. For example, the complete castling rules are not trivial, like with the king not passing through a square currently attacked by an opposing piece https://en.wikipedia.org/wiki/Castling#Requirements https://en.wikipedia.org/wiki/Castling#Requirements and some people may neglect or misimplement en passant https://en.wikipedia.org/wiki/En_passant https://en.wikipedia.org/wiki/En_passant and the rules related to repetitive situations in the end game: https://en.wikipedia.org/wiki/Threefold_repetition https://en.wikipedia.org/wiki/Threefold_repetition https://en.wikipedia.org/wiki/Fifty-move_rule https://en.wikipedia.org/wiki/Fifty-move_rule (Implementing the threefold repetition rule requires maintaining historical state of a different kind than any other chess rule!) I've seen impressive hyperminimalist chess implementations that were missing these things, but that totally felt like real chess almost all of the time.
- trhway 9y ago
  Bugs almost always mean lost money. In block chains it is just more direct and visible.
- AstralStorm 9y ago
  There is a way, reforming everything as an automatic math proof. Because even security is driven by capitalism sort term gains almost nobody does this. It takes time and sometimes serious math skills.
DyslexicAtheist 9y ago
exactly, it's a problem with tooling that could have been prevented. Good points by Matthieu Suiche here going deeper into why: https://twitter.com/msuiche/status/928238570162102273 https://twitter.com/msuiche/status/928238570162102273

tom_mellior 9y ago

> He posted a list of contract addresses in the github issue, most of them look like ICO wallets What are you talking about? Do you mean this issue: https://github.com/paritytech/parity/issues/6995 https://github.com/paritytech/parity/issues/6995 ? What list are you referring to?

arez 9y ago

Just to make one thing clear, you're just assuming. The guy clearly stated that he just tried out different things and never really intended to steal something. If you give out an API make sure that I can't break it by calling it, otherwise it's your fault not mine. The guy seemed also pretty nervous in the gitter channel, he asked if he really broke something and if he gets arrested.

shp0ngle 9y ago

He claimed he tried it, thinking it can't go through. And it seems plausible, since you he was researching similar attacks from the past. He had no reason to make the github issue afterwards, if he was a blackhat who knew what he was doing. His entire presentation doesn't seem like that. (Or even like "someone who is trying for no real reason to try to look innocent". He didn't have to be public at all.)