diff --git a/scripts/build/protobuf.mk b/scripts/build/protobuf.mk
index 25d98b3f9538..7bcd7f60dbc3 100644
--- a/scripts/build/protobuf.mk
+++ b/scripts/build/protobuf.mk
@@ -1,4 +1,4 @@
-protoVer=0.15.2
+protoVer=0.15.3
 protoImageName=ghcr.io/cosmos/proto-builder:$(protoVer)
 protoImage=$(DOCKER) run --rm -v $(CURDIR):/workspace --workdir /workspace $(protoImageName)
 
diff --git a/simapp/sim_test.go b/simapp/sim_test.go
index a4fa3cd02d22..50c304a0d27f 100644
--- a/simapp/sim_test.go
+++ b/simapp/sim_test.go
@@ -147,7 +147,7 @@ func TestAppSimulationAfterImport(t *testing.T) {
 				BalanceSource: app.BankKeeper,
 			}
 		}
-		ti.Cfg.InitialBlockHeight = int(exported.Height)
+		ti.Cfg.InitialBlockHeight = uint64(exported.Height)
 		simsx.RunWithSeed(t, ti.Cfg, NewSimApp, importGenesisStateFactory, ti.Cfg.Seed, ti.Cfg.FuzzSeed)
 	})
 }