KIP-1287 — Disallow sendOffsetsToTransaction from committing offsets for unassigned partitions

Discussion TransactionsBroker

Enforces partition assignment validation in the broker for KafkaProducer.sendOffsetsToTransaction(), rejecting transactional offset commits for partitions not assigned to the requesting consumer group member. The broker currently verifies the member's epoch but does not check whether the committed partitions are actually assigned to that member, allowing a valid-epoch member to maliciously or accidentally overwrite offsets for partitions it does not own.

Protocol Impact

OffsetCommit · TxnOffsetCommit

Details