CVE-2021-41138

Description

Frontier is Substrate's Ethereum compatibility layer. In the newly introduced signed Frontier-specific extrinsic for `pallet-ethereum`, a large part of transaction validation logic was only called in transaction pool validation, but not in block execution. Malicious validators can take advantage of this to put invalid transactions into a block. The attack is limited in that the signature is always validated, and the majority of the validation is done again in the subsequent `pallet-evm` execution logic. However, do note that a chain ID replay attack was possible. In addition, spamming attacks are of main concerns, while they are limited by Substrate block size limits and other factors. The issue is patched in commit `146bb48849e5393004be5c88beefe76fdf009aba`.

CvssV3 impact

Version

3.1

VectorString

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

AttackVector

NETWORK

AttackComplexity

LOW

PrivilegesRequired

NONE

UserInteraction

NONE

Scope

UNCHANGED

ConfidentialityImpact

NONE

IntegrityImpact

LOW

AvailabilityImpact

NONE

BaseScore

5.3

BaseSeverity

MEDIUM

CvssV2 impact

AccessComplexity

LOW

ConfidentialityImpact

NONE

AvailabilityImpact

NONE

IntegrityImpact

PARTIAL

BaseScore

5

VectorString

AV:N/AC:L/Au:N/C:N/I:P/A:N

Version

2.0

AccessVector

NETWORK

Authentication

NONE