Babylon Bitcoin Staking Protocol Exposes Consensus Vulnerability, Malicious Validators Can Slow Down Block Production

【ChainNews】The Bitcoin staking protocol Babylon was recently found to have a serious technical vulnerability. Developers disclosed on GitHub that the flaw is located in the BLS voting extension scheme—the purpose of which is for validators to reach consensus on a particular block.

Where is the problem? The vulnerability allows malicious validators to intentionally omit the block hash field when sending voting extensions. It may seem like just a missing field, but the impact is significant. The role of the block hash field is to inform other validators “which specific blocks we support.”

Once this field is omitted, it triggers validator consensus issues during the network’s epoch boundary. Especially at key consensus check nodes at phase boundaries, malicious validators could theoretically cause other validators to crash. If multiple validators are affected simultaneously, the consequences could be severe—the network’s block production rate would slow down noticeably.

The good news is that there have been no observed cases of this vulnerability being exploited so far. However, developers have issued warnings that if not fixed promptly, this type of attack will eventually be abused. For participants in the Babylon ecosystem, this is a risk point that requires close attention.