diff --git a/nixos/modules/installer/tools/nixos-generate-config.pl b/nixos/modules/installer/tools/nixos-generate-config.pl
index c0df2977856e..7c737e84de0a 100644
--- a/nixos/modules/installer/tools/nixos-generate-config.pl
+++ b/nixos/modules/installer/tools/nixos-generate-config.pl
@@ -8,6 +8,7 @@ use File::Basename;
 use File::Slurp;
 use File::stat;
 
+umask(0022);
 
 sub uniq {
     my %seen;