diff --git a/substrate/core/sr-api-macros/Cargo.toml b/substrate/core/sr-api-macros/Cargo.toml
index 05172e5bf8..7981281b27 100644
--- a/substrate/core/sr-api-macros/Cargo.toml
+++ b/substrate/core/sr-api-macros/Cargo.toml
@@ -8,7 +8,7 @@ proc-macro = true
 
 [dependencies]
 quote = "0.6"
-syn = { version = "0.15", features = [ "full", "fold", "extra-traits", "visit" ] }
+syn = { version = "^0.15.22", features = [ "full", "fold", "extra-traits", "visit" ] }
 proc-macro2 = "0.4"
 
 [dev-dependencies]