diff --git a/pkgs/applications/networking/browsers/firefox/packages.nix b/pkgs/applications/networking/browsers/firefox/packages.nix
index a86b39fff728..b4e7c679de2b 100644
--- a/pkgs/applications/networking/browsers/firefox/packages.nix
+++ b/pkgs/applications/networking/browsers/firefox/packages.nix
@@ -125,11 +125,11 @@
 
   firefox-esr-115 = (buildMozillaMach rec {
     pname = "firefox-esr-115";
-    version = "115.14.0esr";
+    version = "115.15.0esr";
     applicationName = "Mozilla Firefox ESR";
     src = fetchurl {
       url = "mirror://mozilla/firefox/releases/${version}/source/firefox-${version}.source.tar.xz";
-      sha512 = "dd40c1fd3cf454dbf33a85d38e47bb0e736ed89b829643653e239f43232441f4e9f3c7876f058ff2e6f19daf2b50a8f2d13274e9a107d8a258a6067d1fc43f54";
+      sha512 = "0df4c498c99cce08903004d2e0f9e977a19f7de86240aa82dba179b60f1d67ca3021eb474f56bddc38035e773eeb5d99bb3e1b0756d9f7583dc8e1f747f477ba";
     };
 
     meta = {