diff --git a/Cargo.lock b/Cargo.lock
index 86f7662a43..e1edeffba6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -11953,9 +11953,9 @@ checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
 
 [[package]]
 name = "syn"
-version = "1.0.103"
+version = "1.0.104"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a864042229133ada95abf3b54fdc62ef5ccabe9515b64717bcb9a1919e59445d"
+checksum = "4ae548ec36cf198c0ef7710d3c230987c2d6d7bd98ad6edc0274462724c585ce"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/pallets/parachain-system/proc-macro/Cargo.toml b/pallets/parachain-system/proc-macro/Cargo.toml
index 1074771126..cb3c7cf32d 100644
--- a/pallets/parachain-system/proc-macro/Cargo.toml
+++ b/pallets/parachain-system/proc-macro/Cargo.toml
@@ -9,7 +9,7 @@ description = "Proc macros provided by the parachain-system pallet"
 proc-macro = true
 
 [dependencies]
-syn = "1.0.103"
+syn = "1.0.104"
 proc-macro2 = "1.0.47"
 quote = "1.0.21"
 proc-macro-crate = "1.2.1"