diff --git a/pkgs/development/php-packages/protobuf/default.nix b/pkgs/development/php-packages/protobuf/default.nix
index c07e71702ff..a5b22e97953 100644
--- a/pkgs/development/php-packages/protobuf/default.nix
+++ b/pkgs/development/php-packages/protobuf/default.nix
@@ -3,8 +3,8 @@
 buildPecl {
   pname = "protobuf";
 
-  version = "3.21.5";
-  sha256 = "sha256-B8ytFyUJ8fLBwHmaKXxfOy0h6tRELjqc5IxUUl/YU5w=";
+  version = "3.21.6";
+  sha256 = "sha256-vyJbWsY/adrMK2PLdu+Zm1paopY+5qct2Y2AS2a70gg=";
 
   buildInputs = [ pcre2 ];