Poison Message

A message in a queue that repeatedly causes processing failures, blocking forward progress and consuming retry budget. Poison messages arise from malformed payloads, schema mismatches, or bugs in consumer code that cause an unhandled exception on every attempt. Message brokers detect poison messages by counting delivery attempts and move them to a dead letter queue after exceeding the maximum retry count, allowing the rest of the queue to process normally while the bad message is quarantined for inspection.