diff --git a/deny.toml b/deny.toml
index e913f98a52..e7c70283ba 100644
--- a/deny.toml
+++ b/deny.toml
@@ -73,6 +73,7 @@ allow = [
     "ISC",
     "MPL-2.0",
     "OpenSSL",
+    "Zlib",
     "Unicode-DFS-2016"
 ]
 # The confidence threshold for detecting a license from license text.