diff --git a/util/test-gen/Cargo.toml b/util/test-gen/Cargo.toml
index a39302937..95de2949e 100644
--- a/util/test-gen/Cargo.toml
+++ b/util/test-gen/Cargo.toml
@@ -13,4 +13,4 @@ quote       = "1.0"
 serde       = "1"
 serde_json  = "1"
 serde_yaml  = "0.8"
-walkdir     = "2"
+walkdir     = "2.5.0"