diff --git a/Cargo.toml b/Cargo.toml
index f0875d5..8d8a231 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,15 +38,15 @@ all-languages = [
 
 [dependencies]
 bitcoin_hashes = { version = "0.11.0", default-features = false }
-rand_core = "0.4.0"
+rand_core = ">=0.4.0, <0.7.0"
 
 unicode-normalization = { version = "=0.1.9", optional = true }
-rand = { version = "0.6.0", optional = true }
+rand = { version = ">=0.6.0, <0.9.0", optional = true }
 serde = { version = "1.0", default-features = false, features = [ "alloc" ], optional = true }
 # Enabling this feature raises the MSRV to 1.51
 zeroize = {version = "1.5", features = ["zeroize_derive"], optional = true}
 
 [dev-dependencies]
-rand = { version = "0.6.0", optional = false }
+rand = { version = "0.8.5", optional = false }
 bitcoin_hashes = "0.11.0" # enable default features for test