diff --git a/deny.toml b/deny.toml
index cfe436d..a619c94 100644
--- a/deny.toml
+++ b/deny.toml
@@ -98,6 +98,7 @@ allow = [
     "OpenSSL",
     "Unicode-DFS-2016",
     "Unlicense",
+    "Zlib",
 ]
 # The confidence threshold for detecting a license from license text.
 # The higher the value, the more closely the license text must be to the