diff --git a/pkg/core/block/block.go b/pkg/core/block/block.go
index 14c39ce51..cee27d060 100644
--- a/pkg/core/block/block.go
+++ b/pkg/core/block/block.go
@@ -227,5 +227,8 @@ func (b *Block) UnmarshalJSON(data []byte) error {
 	b.Base = *base
 	b.Transactions = auxb.Transactions
 	b.ConsensusData = auxb.ConsensusData
+	// Some tests rely on hash presence and we're usually precomputing
+	// other hashes upon deserialization.
+	_ = b.ConsensusData.Hash()
 	return nil
 }