The Ethereum signaling chain underwent a seven-block reorganization today. Here’s what that means and why it could be a security risk.
The Ethereum Signaling Chain, which will be crucial to the Ethereum Merge planned for later this year, has today experienced a potential high-level security risk known as a “reorganization” of the blockchain.
A reorganization, or reorganization, can occur as a result of a network failure, such as a bug or a malicious attack, which temporarily results in a duplicated version of the blockchain. The longer the reorg lasts, the more severe the consequences.
Today’s reorganization event on the Ethereum Signaling Chain spanned seven blocks – the longest such reorganization in years, according to Martin Köppelmann, CEO and co-founder of service provider DeFi Gnosis.
Beacon Chain, launched on December 1, 2020, introduced native staking to the Ethereum blockchain. Staking, which involves committing assets to a network, is how validators qualify to add blocks to the chain, a key tenet of the proof-of-stake consensus model.
Ethereum Merge, formerly known as “Ethereum 2.0,” is a significant and long-awaited upgrade to the current network and will mark its transition from proof of work to proof of stake. The merge, scheduled for August, will combine the Beacon Chain with the Ethereum mainnet. That means problems with the Signaling Chain can further delay the merge.
Köppelmann noted today’s Ethereum reorganization in a Twitter thread, saying it’s proof that more work remains to be done before consolidation.
“This suggests that the current attestation strategy of nodes should be revisited to hopefully create a more stable chain,” he wrote.
One change occurred when two different miners started working to add blocks of transactions of similar difficulty to the chain at the same time. That creates a fork or a duplicate of the blockchain.
The miner who adds the next block must choose which side of the fork is the correct or canonical chain. Once they’re done, the rest will be lost.
The seven-block reorganization means that the last fork that was dropped had a transaction value of seven blocks added to it before the network decided it was not a standard chain. Each block on the Ethereum chain contains between 200 and 300 transactions and is worth about 2 ETH, or about $4,000, according to Etherscan.io.
When there are two competing versions of the blockchain, even if only for a short time, there is a risk that someone could spend the same asset twice.
When this is done maliciously, as with the ZenGo wallet attack in 2020, it is called a double spend attack. In such an attack, the scammers send a transaction with a minimal fee and then immediately override it with a fee increase (so miners are incentivized to verify the transaction). new translation is more profitable than before) and redirect the funds to another address.
But in this case, the underlying and double-spending cause appears to be benign.
The software that miners use has a method to determine which side of the fork to choose — that’s the authentication strategy Köppelmann mentioned.
The Twitter thread has finally caught the attention of some of Ethereum’s core developers. The founder of Ethereum himself, Vitalik Buterin, added some weight to a theory that the problem was with miners running outdated versions of mining software.
It was a timely response.
Last year, Buterin and Georgios Konstantopoulos, Paradigm’s chief technology officer, addressed the reorgs issue in a blog post. In it, they say that a reorganization of more than five blocks could be a sign of a malicious attack.
They explain that one- and two-block short failures always occur due to network latency.
Buterin and Konstantopoulos wrote in the post: “Sometimes bad luck can lead to 2-5 block reassembly. Problems longer than that are almost always caused by network failures, client failures, or malicious attacks.”
But as Prysm developer Terrence Tsao explained in a Twitter thread, today’s event, although it lasted long enough to cause serious concern, could be just another case of bad luck.