diff --git a/core/genesis.go b/core/genesis.go
index 8546f4e37e..4dd6c9ed24 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -364,6 +364,11 @@ func SetupGenesisBlockWithOverride(db ethdb.Database, triedb *triedb.Database, g
 	}
 	newCfg := genesis.chainConfigOrDefault(ghash, storedCfg)
 
+	// Sanity-check the new configuration.
+	if err := newCfg.CheckConfigForkOrder(); err != nil {
+		return nil, common.Hash{}, nil, err
+	}
+
 	// TODO(rjl493456442) better to define the comparator of chain config
 	// and short circuit if the chain config is not changed.
 	compatErr := storedCfg.CheckCompatible(newCfg, head.Number.Uint64(), head.Time)