diff --git a/Cargo.lock b/Cargo.lock
index 580da5ad074c3..084893daa4ee8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -929,7 +929,7 @@ version = "2.0.0"
 dependencies = [
  "ansi_term",
  "node-cli",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-chain-spec",
  "sc-keystore",
  "sp-core",
@@ -4530,7 +4530,7 @@ dependencies = [
  "node-testing",
  "parity-db",
  "parity-util-mem",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-basic-authorship",
  "sc-client-api",
  "sc-transaction-pool",
@@ -4576,7 +4576,7 @@ dependencies = [
  "pallet-transaction-payment",
  "parity-scale-codec",
  "platforms",
- "rand 0.7.3",
+ "rand 0.8.4",
  "regex",
  "remote-externalities",
  "sc-authority-discovery",
@@ -5574,7 +5574,7 @@ dependencies = [
  "pallet-balances",
  "parity-scale-codec",
  "parking_lot 0.11.2",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "sp-arithmetic",
  "sp-core",
@@ -6062,7 +6062,7 @@ dependencies = [
  "pallet-staking-reward-curve",
  "pallet-timestamp",
  "parity-scale-codec",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "sp-core",
  "sp-io",
@@ -7042,7 +7042,6 @@ dependencies = [
  "rand_chacha 0.2.2",
  "rand_core 0.5.1",
  "rand_hc 0.2.0",
- "rand_pcg 0.2.1",
 ]
 
 [[package]]
@@ -7201,15 +7200,6 @@ dependencies = [
  "rand_core 0.4.2",
 ]
 
-[[package]]
-name = "rand_pcg"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "16abd0c1b639e9eb4d7c50c0b8100b0d0f849be2349829c740fe8e6eb4816429"
-dependencies = [
- "rand_core 0.5.1",
-]
-
 [[package]]
 name = "rand_pcg"
 version = "0.3.1"
@@ -7609,7 +7599,7 @@ dependencies = [
  "prost",
  "prost-build",
  "quickcheck",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-client-api",
  "sc-network",
  "sp-api",
@@ -7702,7 +7692,7 @@ dependencies = [
  "log 0.4.14",
  "names",
  "parity-scale-codec",
- "rand 0.7.3",
+ "rand 0.8.4",
  "regex",
  "rpassword",
  "sc-client-api",
@@ -7863,7 +7853,7 @@ dependencies = [
  "num-traits",
  "parity-scale-codec",
  "parking_lot 0.11.2",
- "rand 0.7.3",
+ "rand 0.8.4",
  "rand_chacha 0.2.2",
  "retain_mut",
  "sc-block-builder",
@@ -8262,7 +8252,7 @@ dependencies = [
  "prost",
  "prost-build",
  "quickcheck",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-block-builder",
  "sc-client-api",
  "sc-consensus",
@@ -8318,7 +8308,7 @@ dependencies = [
  "libp2p",
  "log 0.4.14",
  "parking_lot 0.11.2",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-block-builder",
  "sc-client-api",
  "sc-consensus",
@@ -8350,7 +8340,7 @@ dependencies = [
  "once_cell",
  "parity-scale-codec",
  "parking_lot 0.11.2",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-block-builder",
  "sc-client-api",
  "sc-client-db",
@@ -8377,7 +8367,7 @@ dependencies = [
  "futures 0.3.16",
  "libp2p",
  "log 0.4.14",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-utils",
  "serde_json",
  "wasm-timer",
@@ -8500,7 +8490,7 @@ dependencies = [
  "parity-util-mem",
  "parking_lot 0.11.2",
  "pin-project 1.0.10",
- "rand 0.7.3",
+ "rand 0.8.4",
  "sc-block-builder",
  "sc-chain-spec",
  "sc-client-api",
@@ -8628,7 +8618,7 @@ dependencies = [
  "log 0.4.14",
  "parking_lot 0.11.2",
  "pin-project 1.0.10",
- "rand 0.7.3",
+ "rand 0.8.4",
  "serde",
  "serde_json",
  "thiserror",
@@ -9254,7 +9244,7 @@ dependencies = [
  "num-traits",
  "parity-scale-codec",
  "primitive-types",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "serde",
  "sp-debug-derive",
@@ -9440,7 +9430,7 @@ dependencies = [
  "parity-util-mem",
  "parking_lot 0.11.2",
  "primitive-types",
- "rand 0.7.3",
+ "rand 0.8.4",
  "regex",
  "scale-info",
  "schnorrkel",
@@ -9589,7 +9579,7 @@ dependencies = [
  "merlin",
  "parity-scale-codec",
  "parking_lot 0.11.2",
- "rand 0.7.3",
+ "rand 0.8.4",
  "rand_chacha 0.2.2",
  "schnorrkel",
  "serde",
@@ -9609,7 +9599,7 @@ name = "sp-npos-elections"
 version = "4.0.0-dev"
 dependencies = [
  "parity-scale-codec",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "serde",
  "sp-arithmetic",
@@ -9626,7 +9616,7 @@ version = "2.0.0-alpha.5"
 dependencies = [
  "honggfuzz",
  "parity-scale-codec",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "sp-npos-elections",
  "sp-runtime",
@@ -9687,7 +9677,7 @@ dependencies = [
  "parity-scale-codec",
  "parity-util-mem",
  "paste 1.0.6",
- "rand 0.7.3",
+ "rand 0.8.4",
  "scale-info",
  "serde",
  "serde_json",
@@ -9831,7 +9821,7 @@ dependencies = [
  "parity-scale-codec",
  "parking_lot 0.11.2",
  "pretty_assertions",
- "rand 0.7.3",
+ "rand 0.8.4",
  "smallvec 1.7.0",
  "sp-core",
  "sp-externalities",
@@ -10967,7 +10957,7 @@ version = "1.6.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ee73e6e4924fe940354b8d4d98cad5231175d615cd855b758adc658c0aac6a0"
 dependencies = [
- "cfg-if 1.0.0",
+ "cfg-if 0.1.10",
  "rand 0.8.4",
  "static_assertions",
 ]
diff --git a/bin/node/bench/Cargo.toml b/bin/node/bench/Cargo.toml
index 670f6c4d3ed84..56a846b690ed3 100644
--- a/bin/node/bench/Cargo.toml
+++ b/bin/node/bench/Cargo.toml
@@ -33,7 +33,7 @@ hash-db = "0.15.2"
 tempfile = "3.1.0"
 fs_extra = "1"
 hex = "0.4.0"
-rand = { version = "0.7.2", features = ["small_rng"] }
+rand = { version = "0.8.4", features = ["small_rng"] }
 lazy_static = "1.4.0"
 parity-util-mem = { version = "0.10.2", default-features = false, features = [
     "primitive-types",
diff --git a/bin/node/cli/Cargo.toml b/bin/node/cli/Cargo.toml
index 248181ac5c8b8..566640880d6cf 100644
--- a/bin/node/cli/Cargo.toml
+++ b/bin/node/cli/Cargo.toml
@@ -39,7 +39,7 @@ serde = { version = "1.0.132", features = ["derive"] }
 futures = "0.3.16"
 hex-literal = "0.3.4"
 log = "0.4.8"
-rand = "0.7.2"
+rand = "0.8.4"
 structopt = { version = "0.3.25", optional = true }
 
 # primitives
diff --git a/bin/utils/chain-spec-builder/Cargo.toml b/bin/utils/chain-spec-builder/Cargo.toml
index f9bb4f94491a8..d1ce50e9d2a6b 100644
--- a/bin/utils/chain-spec-builder/Cargo.toml
+++ b/bin/utils/chain-spec-builder/Cargo.toml
@@ -20,5 +20,5 @@ sc-chain-spec = { version = "4.0.0-dev", path = "../../../client/chain-spec" }
 node-cli = { version = "3.0.0-dev", path = "../../node/cli" }
 sp-core = { version = "4.1.0-dev", path = "../../../primitives/core" }
 sp-keystore = { version = "0.10.0", path = "../../../primitives/keystore" }
-rand = "0.7.2"
+rand = "0.8.4"
 structopt = "0.3.25"
diff --git a/client/authority-discovery/Cargo.toml b/client/authority-discovery/Cargo.toml
index c6c523fa5eec7..7cbcd4635cbcb 100644
--- a/client/authority-discovery/Cargo.toml
+++ b/client/authority-discovery/Cargo.toml
@@ -27,7 +27,7 @@ libp2p = { version = "0.40.0", default-features = false, features = ["kad"] }
 log = "0.4.8"
 prometheus-endpoint = { package = "substrate-prometheus-endpoint", path = "../../utils/prometheus", version = "0.10.0-dev" }
 prost = "0.9"
-rand = "0.7.2"
+rand = "0.8.4"
 sc-client-api = { version = "4.0.0-dev", path = "../api" }
 sc-network = { version = "0.10.0-dev", path = "../network" }
 sp-authority-discovery = { version = "4.0.0-dev", path = "../../primitives/authority-discovery" }
diff --git a/client/cli/Cargo.toml b/client/cli/Cargo.toml
index 01f5aab25d5fa..98d1a1f30a82a 100644
--- a/client/cli/Cargo.toml
+++ b/client/cli/Cargo.toml
@@ -21,7 +21,7 @@ fdlimit = "0.2.1"
 libp2p = "0.40.0"
 parity-scale-codec = "2.3.1"
 hex = "0.4.2"
-rand = "0.7.3"
+rand = "0.8.4"
 tiny-bip39 = "0.8.2"
 serde_json = "1.0.74"
 sc-keystore = { version = "4.0.0-dev", path = "../keystore" }
diff --git a/client/consensus/babe/Cargo.toml b/client/consensus/babe/Cargo.toml
index e4d66fcad87cc..bc7ced4366293 100644
--- a/client/consensus/babe/Cargo.toml
+++ b/client/consensus/babe/Cargo.toml
@@ -47,7 +47,7 @@ futures = "0.3.9"
 parking_lot = "0.11.2"
 log = "0.4.8"
 schnorrkel = { version = "0.9.1", features = ["preaudit_deprecated"] }
-rand = "0.7.2"
+rand = "0.8.4"
 merlin = "2.0"
 derive_more = "0.99.16"
 retain_mut = "0.1.4"
diff --git a/client/network/Cargo.toml b/client/network/Cargo.toml
index f378b75990cb9..4fc7ab2309c17 100644
--- a/client/network/Cargo.toml
+++ b/client/network/Cargo.toml
@@ -42,7 +42,7 @@ parking_lot = "0.11.2"
 pin-project = "1.0.10"
 prometheus-endpoint = { package = "substrate-prometheus-endpoint", version = "0.10.0-dev", path = "../../utils/prometheus" }
 prost = "0.9"
-rand = "0.7.2"
+rand = "0.8.4"
 sc-block-builder = { version = "0.10.0-dev", path = "../block-builder" }
 sc-client-api = { version = "4.0.0-dev", path = "../api" }
 sc-peerset = { version = "4.0.0-dev", path = "../peerset" }
@@ -70,7 +70,7 @@ libp2p = "0.40.0"
 assert_matches = "1.3"
 libp2p = { version = "0.40.0", default-features = false }
 quickcheck = "1.0.3"
-rand = "0.7.2"
+rand = "0.8.4"
 sp-test-primitives = { version = "2.0.0", path = "../../primitives/test-primitives" }
 sp-tracing = { version = "4.0.0", path = "../../primitives/tracing" }
 substrate-test-runtime = { version = "2.0.0", path = "../../test-utils/runtime" }
diff --git a/client/network/test/Cargo.toml b/client/network/test/Cargo.toml
index 6b6d777e7396e..2ae6729081abb 100644
--- a/client/network/test/Cargo.toml
+++ b/client/network/test/Cargo.toml
@@ -19,7 +19,7 @@ log = "0.4.8"
 parking_lot = "0.11.2"
 futures = "0.3.9"
 futures-timer = "3.0.1"
-rand = "0.7.2"
+rand = "0.8.4"
 libp2p = { version = "0.40.0", default-features = false }
 sp-consensus = { version = "0.10.0-dev", path = "../../../primitives/consensus/common" }
 sc-consensus = { version = "0.10.0-dev", path = "../../consensus/common" }
diff --git a/client/offchain/Cargo.toml b/client/offchain/Cargo.toml
index dd4bdb71f93b6..b2fd4c2b4a587 100644
--- a/client/offchain/Cargo.toml
+++ b/client/offchain/Cargo.toml
@@ -21,7 +21,7 @@ futures = "0.3.16"
 futures-timer = "3.0.2"
 num_cpus = "1.13"
 parking_lot = "0.11.2"
-rand = "0.7.2"
+rand = "0.8.4"
 sc-client-api = { version = "4.0.0-dev", path = "../api" }
 sc-network = { version = "0.10.0-dev", path = "../network" }
 sp-api = { version = "4.0.0-dev", path = "../../primitives/api" }
diff --git a/client/peerset/Cargo.toml b/client/peerset/Cargo.toml
index ac3590630a1eb..9387d04c73fd0 100644
--- a/client/peerset/Cargo.toml
+++ b/client/peerset/Cargo.toml
@@ -22,4 +22,4 @@ serde_json = "1.0.74"
 wasm-timer = "0.2"
 
 [dev-dependencies]
-rand = "0.7.2"
+rand = "0.8.4"
diff --git a/client/service/Cargo.toml b/client/service/Cargo.toml
index f23bf3f55bbfe..b5b0f362bdea5 100644
--- a/client/service/Cargo.toml
+++ b/client/service/Cargo.toml
@@ -26,7 +26,7 @@ thiserror = "1.0.30"
 futures = "0.3.16"
 jsonrpc-pubsub = "18.0"
 jsonrpc-core = "18.0"
-rand = "0.7.3"
+rand = "0.8.4"
 parking_lot = "0.11.2"
 log = "0.4.11"
 futures-timer = "3.0.1"
diff --git a/client/telemetry/Cargo.toml b/client/telemetry/Cargo.toml
index 2417f3c77b761..f81e4c5183693 100644
--- a/client/telemetry/Cargo.toml
+++ b/client/telemetry/Cargo.toml
@@ -21,7 +21,7 @@ wasm-timer = "0.2.5"
 libp2p = { version = "0.40.0", default-features = false, features = ["dns-async-std", "tcp-async-io", "wasm-ext", "websocket"] }
 log = "0.4.8"
 pin-project = "1.0.10"
-rand = "0.7.2"
+rand = "0.8.4"
 serde = { version = "1.0.132", features = ["derive"] }
 serde_json = "1.0.74"
 chrono = "0.4.19"
diff --git a/frame/election-provider-multi-phase/Cargo.toml b/frame/election-provider-multi-phase/Cargo.toml
index 7add94dc76c80..5d62b5ec83ce3 100644
--- a/frame/election-provider-multi-phase/Cargo.toml
+++ b/frame/election-provider-multi-phase/Cargo.toml
@@ -33,7 +33,7 @@ frame-election-provider-support = { version = "4.0.0-dev", default-features = fa
 
 # Optional imports for benchmarking
 frame-benchmarking = { version = "4.0.0-dev", default-features = false, path = "../benchmarking", optional = true }
-rand = { version = "0.7.3", default-features = false, optional = true, features = [
+rand = { version = "0.8.4", default-features = false, optional = true, features = [
 	"alloc",
 	"small_rng",
 ] }
@@ -42,7 +42,7 @@ strum_macros = { optional = true, version = "0.23.1" }
 
 [dev-dependencies]
 parking_lot = "0.11.2"
-rand = { version = "0.7.3" }
+rand = { version = "0.8.4" }
 sp-core = { version = "4.1.0-dev", default-features = false, path = "../../primitives/core" }
 sp-io = { version = "4.0.0-dev", path = "../../primitives/io" }
 sp-npos-elections = { version = "4.0.0-dev", default-features = false, path = "../../primitives/npos-elections" }
diff --git a/frame/session/benchmarking/Cargo.toml b/frame/session/benchmarking/Cargo.toml
index 10a430d52b0a5..6ca1602e0c1d1 100644
--- a/frame/session/benchmarking/Cargo.toml
+++ b/frame/session/benchmarking/Cargo.toml
@@ -13,7 +13,7 @@ readme = "README.md"
 targets = ["x86_64-unknown-linux-gnu"]
 
 [dependencies]
-rand = { version = "0.7.2", default-features = false }
+rand = { version = "0.8.4", default-features = false }
 
 sp-std = { version = "4.0.0", default-features = false, path = "../../../primitives/std" }
 sp-runtime = { version = "4.1.0-dev", default-features = false, path = "../../../primitives/runtime" }
diff --git a/primitives/arithmetic/Cargo.toml b/primitives/arithmetic/Cargo.toml
index b1ec8639248e9..415bdd5071fc6 100644
--- a/primitives/arithmetic/Cargo.toml
+++ b/primitives/arithmetic/Cargo.toml
@@ -27,7 +27,7 @@ serde = { version = "1.0.132", optional = true, features = ["derive"] }
 sp-debug-derive = { version = "4.0.0", default-features = false, path = "../debug-derive" }
 
 [dev-dependencies]
-rand = "0.7.2"
+rand = "0.8.4"
 criterion = "0.3"
 primitive-types = "0.10.1"
 
diff --git a/primitives/core/Cargo.toml b/primitives/core/Cargo.toml
index 83228b9251ddf..549c3bc533971 100644
--- a/primitives/core/Cargo.toml
+++ b/primitives/core/Cargo.toml
@@ -30,7 +30,7 @@ wasmi = { version = "0.9.1", optional = true }
 hash-db = { version = "0.15.2", default-features = false }
 hash256-std-hasher = { version = "0.15.2", default-features = false }
 base58 = { version = "0.2.0", optional = true }
-rand = { version = "0.7.3", optional = true, features = ["small_rng"] }
+rand = { version = "0.8.4", optional = true, features = ["small_rng"] }
 substrate-bip39 = { version = "0.4.4", optional = true }
 tiny-bip39 = { version = "0.8.2", optional = true }
 regex = { version = "1.5.4", optional = true }
@@ -74,7 +74,7 @@ sp-runtime-interface = { version = "4.1.0-dev", default-features = false, path =
 [dev-dependencies]
 sp-serializer = { version = "4.0.0-dev", path = "../serializer" }
 hex-literal = "0.3.4"
-rand = "0.7.2"
+rand = "0.8.4"
 criterion = "0.3.3"
 serde_json = "1.0"
 sp-core-hashing-proc-macro = { version = "4.0.0-dev", path = "./hashing/proc-macro" }
diff --git a/primitives/keystore/Cargo.toml b/primitives/keystore/Cargo.toml
index e918f5d2c6d75..e67530512da6c 100644
--- a/primitives/keystore/Cargo.toml
+++ b/primitives/keystore/Cargo.toml
@@ -25,7 +25,7 @@ sp-core = { version = "4.1.0-dev", path = "../core" }
 sp-externalities = { version = "0.10.0", path = "../externalities", default-features = false }
 
 [dev-dependencies]
-rand = "0.7.2"
+rand = "0.8.4"
 rand_chacha = "0.2.2"
 
 
diff --git a/primitives/npos-elections/Cargo.toml b/primitives/npos-elections/Cargo.toml
index 062f786aaef1c..c3a7feb25e3b9 100644
--- a/primitives/npos-elections/Cargo.toml
+++ b/primitives/npos-elections/Cargo.toml
@@ -24,7 +24,7 @@ sp-runtime = { version = "4.1.0-dev", path = "../runtime", default-features = fa
 
 [dev-dependencies]
 substrate-test-utils = { version = "4.0.0-dev", path = "../../test-utils" }
-rand = "0.7.3"
+rand = "0.8.4"
 
 [features]
 default = ["std"]
diff --git a/primitives/npos-elections/fuzzer/Cargo.toml b/primitives/npos-elections/fuzzer/Cargo.toml
index 17423b624760e..60aacde7abe9a 100644
--- a/primitives/npos-elections/fuzzer/Cargo.toml
+++ b/primitives/npos-elections/fuzzer/Cargo.toml
@@ -17,7 +17,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 codec = { package = "parity-scale-codec", version = "2.0.0", default-features = false, features = ["derive"] }
 scale-info = { version = "1.0", default-features = false, features = ["derive"] }
 honggfuzz = "0.5"
-rand = { version = "0.7.3", features = ["std", "small_rng"] }
+rand = { version = "0.8.4", features = ["std", "small_rng"] }
 sp-npos-elections = { version = "4.0.0-dev", path = ".." }
 sp-runtime = { version = "4.1.0-dev", path = "../../runtime" }
 structopt = "0.3.25"
diff --git a/primitives/runtime/Cargo.toml b/primitives/runtime/Cargo.toml
index e6bb5a1c842e5..676d497d62377 100644
--- a/primitives/runtime/Cargo.toml
+++ b/primitives/runtime/Cargo.toml
@@ -25,7 +25,7 @@ sp-std = { version = "4.0.0", default-features = false, path = "../std" }
 sp-io = { version = "4.0.0", default-features = false, path = "../io" }
 log = { version = "0.4.14", default-features = false }
 paste = "1.0"
-rand = { version = "0.7.2", optional = true }
+rand = { version = "0.8.4", optional = true }
 impl-trait-for-tuples = "0.2.1"
 parity-util-mem = { version = "0.10.2", default-features = false, features = ["primitive-types"] }
 hash256-std-hasher = { version = "0.15.2", default-features = false }
@@ -33,7 +33,7 @@ either = { version = "1.5", default-features = false }
 
 [dev-dependencies]
 serde_json = "1.0.74"
-rand = "0.7.2"
+rand = "0.8.4"
 sp-state-machine = { version = "0.10.0", path = "../state-machine" }
 sp-api = { version = "4.0.0-dev", path = "../api" }
 substrate-test-runtime-client = { version = "2.0.0", path = "../../test-utils/runtime/client" }
diff --git a/primitives/state-machine/Cargo.toml b/primitives/state-machine/Cargo.toml
index c885f99fdb839..641134d20768b 100644
--- a/primitives/state-machine/Cargo.toml
+++ b/primitives/state-machine/Cargo.toml
@@ -25,7 +25,7 @@ sp-core = { version = "4.1.0-dev", path = "../core", default-features = false }
 sp-panic-handler = { version = "4.0.0", path = "../panic-handler", optional = true }
 codec = { package = "parity-scale-codec", version = "2.0.0", default-features = false }
 num-traits = { version = "0.2.8", default-features = false }
-rand = { version = "0.7.2", optional = true }
+rand = { version = "0.8.4", optional = true }
 sp-externalities = { version = "0.10.0", path = "../externalities", default-features = false }
 smallvec = "1.7.0"
 sp-std = { version = "4.0.0", default-features = false, path = "../std" }
@@ -35,7 +35,7 @@ tracing = { version = "0.1.29", optional = true }
 hex-literal = "0.3.4"
 sp-runtime = { version = "4.1.0-dev", path = "../runtime" }
 pretty_assertions = "1.0.0"
-rand = "0.7.2"
+rand = "0.8.4"
 
 [features]
 default = ["std"]