diff --git a/pkgs/by-name/ut/utf8cpp/package.nix b/pkgs/by-name/ut/utf8cpp/package.nix
index e5ee3a2477d3..d0861d2a93bf 100644
--- a/pkgs/by-name/ut/utf8cpp/package.nix
+++ b/pkgs/by-name/ut/utf8cpp/package.nix
@@ -7,13 +7,13 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "utf8cpp";
-  version = "4.2.0";
+  version = "4.2.1";
 
   src = fetchFromGitHub {
     owner = "nemtrif";
     repo = "utfcpp";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-vc7nKVVZ/h6q+dQUNiuXnkcqX7L2CkG6WUiybLNXAjU=";
+    hash = "sha256-/YpP2ZThfOL1O7aunjKYv5TCjVzMnXVGEefmBpRBIGY=";
   };
 
   nativeBuildInputs = [ cmake ];