CVE-2021-42766: Critical severity ethereum vulnerability

Published Oct 20, 2021
·
Updated

The Proof-of-Stake (PoS) Ethereum consensus protocol through 2021-10-19 allows an adversary to cause a denial of service (long-range consensus chain reorganizations), even when this adversary has little stake and cannot influence network message propagation. This can cause a protocol stall, or an increase in the profits of individual validators.

Affected Software

1 affected component
Proof-of-stake Ethereum Project Proof-of-stake Ethereum<=2021-10-19

Event History

Oct 20, 2021
CVE Published
via MITRE·07:27 PM
Data Sourced
via MITRE·07:27 PM
Description
Data Sourced
via NVD·08:15 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-42766?

CVE-2021-42766 is considered a moderate severity vulnerability as it can result in denial of service via long-range chain reorganizations.

2

How do I fix CVE-2021-42766?

To mitigate CVE-2021-42766, users are advised to upgrade their Proof-of-Stake Ethereum implementation to a version released after October 19, 2021.

3

What is the impact of CVE-2021-42766 on Ethereum?

CVE-2021-42766 allows an adversary to potentially stall the Ethereum protocol through chain reorganizations, impacting network reliability.

4

Who is affected by CVE-2021-42766?

Users running any version of the Proof-of-Stake Ethereum software before October 19, 2021 are affected by CVE-2021-42766.

5

What does CVE-2021-42766 mean for Ethereum's Proof-of-Stake consensus?

CVE-2021-42766 highlights a vulnerability in the Proof-of-Stake consensus that could be exploited to disrupt network operations.

Contact

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