Intel

AIKIDO-2025-10225

tendermint-light-client-verifier is vulnerable to Authentication Bypass by Spoofing

Authentication Bypass by SpoofingGHSA-6jrf-4jv4-r9mw

91

Critical Risk

This Affects:

RUSTtendermint-light-client-verifier
0.23.0 - 0.40.2
Fixed in 0.40.3

TL;DR

Affected versions of the tendermint-rs package are vulnerable to a critical flaw in the light client implementation due to improper validation of validator identities. Specifically, the client fails to ensure that a validator’s address is correctly derived from its public key when counting votes. This allows an attacker to spoof validator signatures and forge a malicious block that appears to be signed by a 2/3+ majority, causing the light client to incorrectly trust and accept the block.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range.

Background info

tendermint-light-client-verifier is vulnerable to Authentication Bypass by Spoofing in versions 0.23.0 - 0.40.2.

How to fix this

Upgrade the tendermint-light-client-verifier library to the patch version.

Background Info