Summary: Implementation bug in the go client may lead to invalid state

Affected client versions: Latest (unpatched) versions of Go client; v1.1.2, v1.0.4 tags and develop, master branches before September 9.

Likelihood: Low

Severity: High

Impact: High

Details: Go ethereum client does not correctly restore state of execution environment when a transaction goes out-of-gas if - within the same block - a contract was suicided. This would result in an invalid copy operation of the state object; flagging the contract as not deleted. This operation would cause a consensus issue between the other implementations.

Effects on expected chain reorganisation depth: none

Remedial action taken by Ethereum: Provision of hotfixes as below.

Proposed temporary workaround: Use Python or C++ client

If using the PPA: sudo apt-get update then sudo apt-get upgrade

If using brew: brew update then brew reinstall ethereum

If using a windows binary: download the updated binary from https://github.com/ethereum/go-ethereum/releases/tag/v1.1.3

Master branch commit: https://github.com/ethereum/go-ethereum/commit/9ebe787d3afe35902a639bf7c1fd68d1e591622a