DeadLetterPublishingRecovererFactory reads the retry_topic-original-timestamp header from an inbound ConsumerRecord and passes its raw bytes directly to new BigInteger(header.value()) with no length or format validation. A Kafka producer with write access to a topic consumed by a @RetryableTopic listener can attach a malformed header (e.g. a zero-length byte array), causing a NumberFormatException in the destination resolver during recovery. This aborts dead-letter publication, the error handler seeks back to the failed offset, and the cycle repeats indefinitely, stalling partition consumption.