diff --git a/pkgs/tools/networking/ppp/default.nix b/pkgs/tools/networking/ppp/default.nix
index 90a4b988c3f..d07770260ff 100644
--- a/pkgs/tools/networking/ppp/default.nix
+++ b/pkgs/tools/networking/ppp/default.nix
@@ -34,7 +34,9 @@ stdenv.mkDerivation rec {
   '';
 
   postFixup = ''
-    substituteInPlace $out/bin/{pon,poff,plog} --replace "/usr/sbin" "$out/bin"
+    for tgt in pon poff plog; do
+      substituteInPlace "$out/bin/$tgt" --replace "/usr/sbin" "$out/bin"
+    done
   '';
 
   meta = {