diff --git a/cumulus/Cargo.lock b/cumulus/Cargo.lock
index 048b606a0a..8a7bde2365 100644
--- a/cumulus/Cargo.lock
+++ b/cumulus/Cargo.lock
@@ -12047,9 +12047,9 @@ checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
 
 [[package]]
 name = "syn"
-version = "1.0.90"
+version = "1.0.91"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "704df27628939572cd88d33f171cd6f896f4eaca85252c6e0a72d8d8287ee86f"
+checksum = "b683b2b825c8eef438b77c36a06dc262294da3d5a5813fac20da149241dcd44d"
 dependencies = [
  "proc-macro2",
  "quote",
diff --git a/cumulus/pallets/parachain-system/proc-macro/Cargo.toml b/cumulus/pallets/parachain-system/proc-macro/Cargo.toml
index 7b2d58fbd3..3db74cc90d 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 = "1.0.90"
+syn = "1.0.91"
 proc-macro2 = "1.0.36"
 quote = "1.0.17"
 proc-macro-crate = "1.1.3"