diff --git a/pkgs/os-specific/linux/kernel/linux-testing.nix b/pkgs/os-specific/linux/kernel/linux-testing.nix
index c785ad4a4f77..e4dac2932bce 100644
--- a/pkgs/os-specific/linux/kernel/linux-testing.nix
+++ b/pkgs/os-specific/linux/kernel/linux-testing.nix
@@ -1,13 +1,13 @@
 { stdenv, hostPlatform, fetchurl, perl, buildLinux, libelf, utillinux, ... } @ args:
 
 import ./generic.nix (args // rec {
-  version = "4.15-rc3";
-  modDirVersion = "4.15.0-rc3";
+  version = "4.15-rc4";
+  modDirVersion = "4.15.0-rc4";
   extraMeta.branch = "4.15";
 
   src = fetchurl {
     url = "https://git.kernel.org/torvalds/t/linux-${version}.tar.gz";
-    sha256 = "1rbyh5phx6mfr3wrz3q33gj8bgw2r76hvbzhvq1ya7fw54jjnz98";
+    sha256 = "13mz21pdqk17hrwga9246cj9bkcz3xmmg0cb4mrbsrb1nv4niv0k";
   };
 
   # Should the testing kernels ever be built on Hydra?