diff --git a/tfexec/internal/e2etest/util_test.go b/tfexec/internal/e2etest/util_test.go
index adfbd3d..026b141 100644
--- a/tfexec/internal/e2etest/util_test.go
+++ b/tfexec/internal/e2etest/util_test.go
@@ -34,6 +34,7 @@
 		testutil.Latest013,
 		testutil.Latest014,
 		testutil.Latest015,
+		testutil.Latest_v1,
 	}
 	if override := os.Getenv("TFEXEC_E2ETEST_VERSIONS"); override != "" {
 		versions = strings.Split(override, ",")
diff --git a/tfexec/internal/testutil/tfcache.go b/tfexec/internal/testutil/tfcache.go
index c206b09..4f3bcd3 100644
--- a/tfexec/internal/testutil/tfcache.go
+++ b/tfexec/internal/testutil/tfcache.go
@@ -13,7 +13,8 @@
 	Latest012 = "0.12.31"
 	Latest013 = "0.13.7"
 	Latest014 = "0.14.11"
-	Latest015 = "0.15.1"
+	Latest015 = "0.15.5"
+	Latest_v1 = "1.0.0"
 )
 
 const appendUserAgent = "tfexec-testutil"