diff --git a/pkgs/applications/networking/browsers/firefox/packages/firefox.nix b/pkgs/applications/networking/browsers/firefox/packages/firefox.nix
index bf91a6453515..6569d19bd289 100644
--- a/pkgs/applications/networking/browsers/firefox/packages/firefox.nix
+++ b/pkgs/applications/networking/browsers/firefox/packages/firefox.nix
@@ -9,10 +9,10 @@
 
 buildMozillaMach rec {
   pname = "firefox";
-  version = "140.0.2";
+  version = "140.0.4";
   src = fetchurl {
     url = "mirror://mozilla/firefox/releases/${version}/source/firefox-${version}.source.tar.xz";
-    sha512 = "11d3295c82835668f43a888bd5aada22248776e033aecc7558348e6ee26626bf4b65bbaae2680f7285a6b2b6209ec5d4aea453f1e0603544cd48bf45c735b2ea";
+    sha512 = "3de7c0871b8a45683f5c226fb3e91e597e8f89ef154b208b2a57c4d3ea9f39cb5c69ecbd5eca3b6da68d3775688d2289c1360c7d110c67bb1be1cf26ef8cf36d";
   };
 
   meta = {