diff --git a/Cargo.lock b/Cargo.lock
index 7c8ee471d7d6..aa4dad785e70 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4323,6 +4323,18 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "merlin"
+version = "3.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "58c38e2799fc0978b65dfff8023ec7843e2330bb462f19198840b34b6582397d"
+dependencies = [
+ "byteorder",
+ "keccak",
+ "rand_core 0.6.3",
+ "zeroize",
+]
+
 [[package]]
 name = "mick-jaeger"
 version = "0.1.8"
@@ -6467,7 +6479,7 @@ dependencies = [
  "kvdb",
  "kvdb-memorydb",
  "lru 0.7.5",
- "merlin",
+ "merlin 3.0.0",
  "parity-scale-codec",
  "parking_lot 0.12.0",
  "polkadot-node-jaeger",
@@ -8795,7 +8807,7 @@ dependencies = [
  "fork-tree",
  "futures 0.3.21",
  "log",
- "merlin",
+ "merlin 2.0.1",
  "num-bigint",
  "num-rational 0.2.4",
  "num-traits",
@@ -9593,7 +9605,7 @@ dependencies = [
  "arrayvec 0.5.2",
  "curve25519-dalek 2.1.3",
  "getrandom 0.1.16",
- "merlin",
+ "merlin 2.0.1",
  "rand 0.7.3",
  "rand_core 0.5.1",
  "sha2 0.8.2",
@@ -10138,7 +10150,7 @@ version = "0.10.0-dev"
 source = "git+https://github.com/paritytech/substrate?branch=master#4aec7b4d0647c20f0e6b769b41bfec435dcfeced"
 dependencies = [
  "async-trait",
- "merlin",
+ "merlin 2.0.1",
  "parity-scale-codec",
  "scale-info",
  "serde",
@@ -10201,7 +10213,7 @@ dependencies = [
  "lazy_static",
  "libsecp256k1",
  "log",
- "merlin",
+ "merlin 2.0.1",
  "num-traits",
  "parity-scale-codec",
  "parity-util-mem",
@@ -10358,7 +10370,7 @@ source = "git+https://github.com/paritytech/substrate?branch=master#4aec7b4d0647
 dependencies = [
  "async-trait",
  "futures 0.3.21",
- "merlin",
+ "merlin 2.0.1",
  "parity-scale-codec",
  "parking_lot 0.12.0",
  "schnorrkel",
diff --git a/node/core/approval-voting/Cargo.toml b/node/core/approval-voting/Cargo.toml
index 74898ffaf74d..9e6635387dfe 100644
--- a/node/core/approval-voting/Cargo.toml
+++ b/node/core/approval-voting/Cargo.toml
@@ -11,7 +11,7 @@ parity-scale-codec = { version = "3.1.2", default-features = false, features = [
 gum = { package = "tracing-gum", path = "../../gum" }
 bitvec = { version = "1.0.0", default-features = false, features = ["alloc"] }
 lru = "0.7"
-merlin = "2.0"
+merlin = "3.0"
 schnorrkel = "0.9.1"
 kvdb = "0.11.0"
 derive_more = "0.99.17"