diff --git a/nixos/modules/system/boot/initrd-ssh.nix b/nixos/modules/system/boot/initrd-ssh.nix
index cdeff4845948..8b3dc2d90eb3 100644
--- a/nixos/modules/system/boot/initrd-ssh.nix
+++ b/nixos/modules/system/boot/initrd-ssh.nix
@@ -118,7 +118,7 @@ in
         echo ${escapeShellArg key} >> /root/.ssh/authorized_keys
       '') cfg.authorizedKeys)}
 
-      dropbear -s -j -k -E -m -p ${toString cfg.port} ${optionalString (cfg.hostRSAKey == null && cfg.hostDSSKey == null && cfg.hostECDSAKey == null) "-R"}
+      dropbear -s -j -k -E -p ${toString cfg.port} ${optionalString (cfg.hostRSAKey == null && cfg.hostDSSKey == null && cfg.hostECDSAKey == null) "-R"}
     '';
 
     boot.initrd.secrets =
diff --git a/pkgs/tools/networking/dropbear/default.nix b/pkgs/tools/networking/dropbear/default.nix
index b7ef3b8fa75b..709fb9540d16 100644
--- a/pkgs/tools/networking/dropbear/default.nix
+++ b/pkgs/tools/networking/dropbear/default.nix
@@ -4,11 +4,11 @@
 }:
 
 stdenv.mkDerivation rec {
-  name = "dropbear-2018.76";
+  name = "dropbear-2017.75";
 
   src = fetchurl {
     url = "http://matt.ucc.asn.au/dropbear/releases/${name}.tar.bz2";
-    sha256 = "0rgavbzw7jrs5wslxm0dnwx2m409yzxd9hazd92r7kx8xikr3yzj";
+    sha256 = "1309cm2aw62n9m3h38prvgsqr8bj85hfasgnvwkd42cp3k5ivg3c";
   };
 
   dontDisableStatic = enableStatic;