The current Sarama website says that it supports from Kafka 0.11 to Kafka 1.1.0, but it's not clear to me what version of Sarama is bundled into the latest available version of Filebeat.
We're using Sarama 1.12, which claimed to support up to Kafka 0.10.2, the latest version at the time it was released.
However, Kafka is backwards compatible, a newer cluster (1.1.0) is able to deal with older clients (filebeat).