The Stellar Development Foundation (SDF), the entity behind the Stellar blockchain, opted to disarm their validators ahead of a vote to upgrade the network on Jan 30, after discovering a bug in Stellar Core v20.1.0.

“As the network introduces the biggest protocol change to date, it’s important to have broad consensus at the vote, but also in the lead up to it — everyone needs to be ready,” said the SDF in a Jan. 27 blog post.

The bug in question could impact applications and services that use fee bumps for Soroban transactions if or when the Mainnet upgrades to Protocol 20. In a GitHub post, Stellar developers explained that the unused refundable fee is sent back to the source account of the inner transaction, instead of the source of the fee-bump transaction as intended. 

Although the SDF determined that the bug itself poses “little risk” to the phased rollout plan for the Protocol 20 upgrade, several network participants on Stellar’s developer Discord and mailing list encouraged the Foundation to change course and prevent its validators from voting entirely. 

However, they noted that other validators can still make their own decisions on whether or not to vote for the Protocol 20 upgrade and quorum could still be achieved by the end of the month. The SDF assured users that, either way, work on resolving the bug will continue. 

According to data from, there are currently 42.5 validator nodes on the Stellar blockchain. 

If validators opt to postpone the upgrade, we will coordinate to determine a future vote date once a new version of Stellar Core that contains a bug fix is released. That release should be available within the next two weeks,” said the SDF.