Shallow copy bug in geth in github.com/ethereum/go-ethereum

Open Source Vulnerabilities CVE-2020-26241

Go Ethereum, or "Geth", is the official Golang implementation of the Ethereum protocol. This is a Consensus vulnerability in Geth before version 1.9.17 which can be used to cause a chain-split where vulnerable nodes reject the canonical chain. Geth's pre-compiled dataCopy (at 0x00...04) contract did a shallow copy on invocation. An attacker could deploy a contract that writes X to an EVM memory region R, then calls 0x00..04 with R as an argument, then overwrites R to Y, and finally invokes the RETURNDATACOPY opcode. When this contract is invoked, a consensus-compliant node would push X on the EVM stack, whereas Geth would push Y. This is fixed in version 1.9.17.

Open Source Vulnerabilities GHSA-69v6-xc2j-r2jf

### Impact This is a Consensus vulnerability, which can be used to cause a chain-split where vulnerable nodes reject the canonical chain. Geth’s pre-compiled `dataCopy` (at `0x00...04`) contract did a shallow copy on invocation. An attacker could deploy a contract that - writes `X` to an EVM memory region `R`, - calls `0x00..04` with `R` as an argument, - overwrites `R` to `Y`, - and finally invokes the `RETURNDATACOPY` opcode. When this contract is invoked, a consensus-compliant node would push `X` on the EVM stack, whereas Geth would push `Y`. ### Patches No standalone patches have been made. ### Workarounds Upgrade to `1.9.17` or higher. ### References https://blog.ethereum.org/2020/11/12/geth_security_release/ ### For more information If you have any questions or comments about this advisory: * Open an issue in [go-ethereum](https://github.com/ethereum/go-ethereum) * Email us at [[email protected]](mailto:[email protected])

Open Source Vulnerabilities GO-2022-0771

Shallow copy bug in geth in github.com/ethereum/go-ethereum