diff --git a/Cargo.lock b/Cargo.lock
index 43f67695faa11..a017b15e0d270 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4363,6 +4363,18 @@ 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 0.6.4",
+ "zeroize",
+]
+
 [[package]]
 name = "minimal-lexical"
 version = "0.2.1"
@@ -8109,7 +8121,7 @@ dependencies = [
  "fork-tree",
  "futures",
  "log",
- "merlin",
+ "merlin 3.0.0",
  "num-bigint",
  "num-rational",
  "num-traits",
@@ -9206,7 +9218,7 @@ 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",
@@ -9793,7 +9805,7 @@ name = "sp-consensus-babe"
 version = "0.10.0-dev"
 dependencies = [
  "async-trait",
- "merlin",
+ "merlin 3.0.0",
  "parity-scale-codec",
  "scale-info",
  "serde",
@@ -9862,7 +9874,7 @@ dependencies = [
  "lazy_static",
  "libsecp256k1",
  "log",
- "merlin",
+ "merlin 3.0.0",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "primitive-types",
@@ -10010,7 +10022,7 @@ version = "0.13.0"
 dependencies = [
  "async-trait",
  "futures",
- "merlin",
+ "merlin 3.0.0",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "rand 0.7.3",
diff --git a/client/consensus/babe/Cargo.toml b/client/consensus/babe/Cargo.toml
index f0ff0080fd610..bff1264c935f2 100644
--- a/client/consensus/babe/Cargo.toml
+++ b/client/consensus/babe/Cargo.toml
@@ -18,7 +18,7 @@ async-trait = "0.1.57"
 codec = { package = "parity-scale-codec", version = "3.2.2", features = ["derive"] }
 futures = "0.3.21"
 log = "0.4.17"
-merlin = "2.0"
+merlin = "3.0"
 num-bigint = "0.4.3"
 num-rational = "0.4.1"
 num-traits = "0.2.8"
diff --git a/primitives/consensus/babe/Cargo.toml b/primitives/consensus/babe/Cargo.toml
index 334fff2811941..bf1ec9aafcf60 100644
--- a/primitives/consensus/babe/Cargo.toml
+++ b/primitives/consensus/babe/Cargo.toml
@@ -15,7 +15,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 [dependencies]
 async-trait = { version = "0.1.57", optional = true }
 codec = { package = "parity-scale-codec", version = "3.2.2", default-features = false }
-merlin = { version = "2.0", default-features = false }
+merlin = { version = "3.0", default-features = false }
 scale-info = { version = "2.1.1", default-features = false, features = ["derive"] }
 serde = { version = "1.0.136", features = ["derive"], optional = true }
 sp-api = { version = "4.0.0-dev", default-features = false, path = "../../api" }
diff --git a/primitives/core/Cargo.toml b/primitives/core/Cargo.toml
index f9a522178f4c8..7ae1e9640eb16 100644
--- a/primitives/core/Cargo.toml
+++ b/primitives/core/Cargo.toml
@@ -51,7 +51,7 @@ schnorrkel = { version = "0.9.1", features = [
 	"u64_backend",
 ], default-features = false, optional = true }
 libsecp256k1 = { version = "0.7", default-features = false, features = ["static-context"], optional = true }
-merlin = { version = "2.0", default-features = false, optional = true }
+merlin = { version = "3.0", default-features = false, optional = true }
 secp256k1 = { version = "0.24.0", default-features = false, features = ["recovery", "alloc"], optional = true }
 ss58-registry = { version = "1.34.0", default-features = false }
 sp-core-hashing = { version = "5.0.0", path = "./hashing", default-features = false, optional = true }
diff --git a/primitives/keystore/Cargo.toml b/primitives/keystore/Cargo.toml
index 9386cb5d104d2..180560512e330 100644
--- a/primitives/keystore/Cargo.toml
+++ b/primitives/keystore/Cargo.toml
@@ -16,7 +16,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 async-trait = "0.1.57"
 codec = { package = "parity-scale-codec", version = "3.2.2", default-features = false, features = ["derive"] }
 futures = "0.3.21"
-merlin = { version = "2.0", default-features = false }
+merlin = { version = "3.0", default-features = false }
 parking_lot = { version = "0.12.1", default-features = false }
 schnorrkel = { version = "0.9.1", default-features = false, features = ["preaudit_deprecated", "u64_backend"] }
 serde = { version = "1.0", optional = true }