diff --git a/deny.toml b/deny.toml
index 11e01f26782f..ff831b533bd4 100644
--- a/deny.toml
+++ b/deny.toml
@@ -231,10 +231,10 @@ skip-tree = [
 [sources]
 # Lint level for what to happen when a crate from a crate registry that is not
 # in the allow list is encountered
-unknown-registry = "warn"
+unknown-registry = "deny"
 # Lint level for what to happen when a crate from a git repository that is not
 # in the allow list is encountered
-unknown-git = "warn"
+unknown-git = "deny"
 # List of URLs for allowed crate registries. Defaults to the crates.io index
 # if not specified. If it is specified but empty, no registries are allowed.
 allow-registry = ["https://github.com/rust-lang/crates.io-index"]