diff --git a/pkgs/os-specific/linux/kernel/linux-grsecurity.nix b/pkgs/os-specific/linux/kernel/linux-grsecurity.nix
index 779a80208d15..8d4ae1d10602 100644
--- a/pkgs/os-specific/linux/kernel/linux-grsecurity.nix
+++ b/pkgs/os-specific/linux/kernel/linux-grsecurity.nix
@@ -1,12 +1,12 @@
 { stdenv, fetchurl, perl, buildLinux, ... } @ args:
 
 import ./generic.nix (args // rec {
-  version = "4.9.22";
+  version = "4.9.23";
   extraMeta.branch = "4.9";
 
   src = fetchurl {
     url = "mirror://kernel/linux/kernel/v4.x/linux-${version}.tar.xz";
-    sha512 = "1hnbadbfvsqsdp7rd1zy07wi3wvryfr0cibk7jq0f35zfkpf4qyry9l1p28kca64p6zg2qb2arnr2p2qgbpx8dzsnwq6q072qddq4hg";
+    sha512 = "0nf68gpgkxglrrrpvadbbc66bpd7vfl3820z5yv4zpz8lx56y02w4pn166aqffwxr60xw15mkp65ircnhclz9qcv4778wkbwd7pv1k0";
   };
 
   kernelPatches = args.kernelPatches;
diff --git a/pkgs/os-specific/linux/kernel/patches.nix b/pkgs/os-specific/linux/kernel/patches.nix
index 2f0073ef25fa..38483e8d765a 100644
--- a/pkgs/os-specific/linux/kernel/patches.nix
+++ b/pkgs/os-specific/linux/kernel/patches.nix
@@ -100,9 +100,9 @@ rec {
   };
 
   grsecurity_testing = grsecPatch
-    { kver   = "4.9.22";
-      grrev  = "201704120836";
-      sha512 = "3320r4myn9y5wf2i2aybl1aapcl9sms0z6p343xh5x0pvaphsjhksnh7cndrq0qxc7fqdwzh9nw1vf84qy02cg5nf8bq025jpkfp7qh";
+    { kver   = "4.9.23";
+      grrev  = "201704181901";
+      sha512 = "1cwiqrr707iz6rv72ikj6h3r6r5x325qlq21gsacsxslvk8igmj97amnqylsg32bjj0za072cb8lqf0zvrv7xzvlc9zjcwridd79vc2";
     };
 
   # This patch relaxes grsec constraints on the location of usermode helpers,