diff --git a/cumulus/Cargo.lock b/cumulus/Cargo.lock
index e251fe4ac9..a5884cf190 100644
--- a/cumulus/Cargo.lock
+++ b/cumulus/Cargo.lock
@@ -464,7 +464,7 @@ checksum = "0e97ce7de6cf12de5d7226c73f5ba9811622f4db3a5b91b55c53e987e5f91cba"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -475,7 +475,7 @@ checksum = "b9ccdd8f2a161be9bd5c023df56f1b2a0bd1d83872ae53b71a84a12c9bf6e842"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -610,7 +610,7 @@ dependencies = [
  "regex",
  "rustc-hash",
  "shlex",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -1559,7 +1559,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -2490,7 +2490,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -3446,7 +3446,7 @@ checksum = "5e9a1f9f7d83e59740248a6e14ecf93929ade55027844dfcea78beafccc15745"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -3457,7 +3457,7 @@ checksum = "48016319042fb7c87b78d2993084a831793a897a5cd1a2a67cab9d1eeb4b7d76"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -3613,7 +3613,7 @@ dependencies = [
  "fs-err",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -3884,7 +3884,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -4001,7 +4001,7 @@ dependencies = [
  "proc-macro-warning",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -4013,7 +4013,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -4023,7 +4023,7 @@ source = "git+https://github.com/paritytech/substrate?branch=master#2bc071f33da2
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -4192,7 +4192,7 @@ checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -7082,7 +7082,7 @@ source = "git+https://github.com/paritytech/substrate?branch=master#2bc071f33da2
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -7718,7 +7718,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -10136,7 +10136,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ceca8aaf45b5c46ec7ed39fff75f57290368c1846d33d24a122ca81416ab058"
 dependencies = [
  "proc-macro2",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -10211,7 +10211,7 @@ checksum = "70550716265d1ec349c41f70dd4f964b4fd88394efe4405f0c1da679c4799a07"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -11185,7 +11185,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -12152,7 +12152,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -12477,7 +12477,7 @@ checksum = "8c805777e3930c8883389c602315a24224bcc738b63905ef87cd1420353ea93e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -12785,7 +12785,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -13027,7 +13027,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "sp-core-hashing",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -13046,7 +13046,7 @@ source = "git+https://github.com/paritytech/substrate?branch=master#2bc071f33da2
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -13257,7 +13257,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -13443,7 +13443,7 @@ dependencies = [
  "parity-scale-codec",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -13963,7 +13963,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -14012,9 +14012,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.16"
+version = "2.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a6f671d4b5ffdb8eadec19c0ae67fe2639df8684bd7bc4b83d986b8db549cf01"
+checksum = "32d41677bcbe24c20c52e7c70b0d8db04134c5d1066bf98662e2871ad200ea3e"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -14125,7 +14125,7 @@ checksum = "f9456a42c5b0d803c8cd86e73dd7cc9edd429499f37a3550d286d5e86720569f"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -14305,7 +14305,7 @@ checksum = "630bdcf245f78637c13ec01ffae6187cca34625e8c63150d424b59e55af2675e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -14505,7 +14505,7 @@ dependencies = [
  "proc-macro-crate",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
@@ -16236,7 +16236,7 @@ dependencies = [
  "Inflector",
  "proc-macro2",
  "quote",
- "syn 2.0.16",
+ "syn 2.0.18",
 ]
 
 [[package]]
diff --git a/cumulus/pallets/parachain-system/proc-macro/Cargo.toml b/cumulus/pallets/parachain-system/proc-macro/Cargo.toml
index 5caf7cb7b3..cd47fef9e0 100644
--- a/cumulus/pallets/parachain-system/proc-macro/Cargo.toml
+++ b/cumulus/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 = "2.0.15"
+syn = "2.0.18"
 proc-macro2 = "1.0.59"
 quote = "1.0.28"
 proc-macro-crate = "1.3.1"