Sep 23, 2016 at 11:20 // News

Daniel Dabek Author

September 23, 2016 - The Ethereum Network fixes a new Denial of Service attack that causes block confirmation times to increase by 300%.

A newly found Denial of Service (DoS) attack spams miners with an EXTCODESIZE operation which causes the mining software to get information from the hard disk. This spam geared down miners from being able to confirm blocks at the usual rate of every 15 seconds due to the added operations that the transaction spam causes.



The Ethereum Network core developers have noticed the issue and addressed fixing it by suggesting miners decrease hard disk read times and reducing transaction processing time. For the long-term, Vitalik Buterin released a blog post that proposes a modification that directly addresses the EXTCODESIZE:



“Adding an additional cache for EXTCODESIZE specifically (as it is likely that EXTCODESIZE reads are several times slower than other IO-heavy operations since the contracts that are being read are ~18 KB long).”







“The price of Ethereum was sold down just a day before the attack had been launched. Prices have since then recovered from lows. It is possible that this was a calculated sell off, and with the simple fix to the mining software Ethereum should be back to normal operational status,” says Daniel Dabek, Founder of alt-coin trading community Safe Exchange.