Close Menu


    Ethereum

    Security alarm [Implementation of BLOCKHASH instruction in C++ and Go clients can potentially cause consensus issue – Fixed. Please update.]

    msmarkBy No Comments1 Min Read

    summary: Incorrect implementation of BLOCKHASH can lead to chain reorganization leading to consensus problems

    Affected configurations: All versions of geth up to 1.1.3 and 1.2.2. All versions prior to 1.0.0.

    Probability: a little

    Danger: Mediation

    impact: Mediation

    details: Both C++ (eth) and Go (geth) clients have a faulty implementation of edge state in the Ethereum virtual machine, specifically the chain that the BLOCKHASH instruction uses to retrieve the block hash. This edge condition is unlikely to occur on a live network as it will only be triggered in certain types of chain reorganizations (nodes executing BLOCKHASH(N – 1) where N is the head of a not-yet-created non-core subchain that has been reorganized to become the primary chain (best/longest) but this will be done after the block is processed).

    Pythium is not affected.

    Effects on the expected depth of chain reorganization: no one

    Remedial action taken by Ethereum: Provide hotfixes as follows.

    Geth:

    Power Purchase Agreement: sudo apt-get update then sudo apt-get upgrade

    Drink: Update brew and then reinstall Ethereum

    Windows: Download the updated binary file from https://github.com/ethereum/go-ethereum/releases/tag/v1.2.3

    Build from source:

    git fetch origin && git checkout origin/master




    Ethics:

    Power Purchase Agreement: https://gavofyork.gitbooks.io/turboethereum/content/chapter1.html

    Share.

    Related Posts