diff --git a/pkgs/top-level/perl-packages.nix b/pkgs/top-level/perl-packages.nix
index a6e747abbeca..e0ca3b733b44 100644
--- a/pkgs/top-level/perl-packages.nix
+++ b/pkgs/top-level/perl-packages.nix
@@ -1350,6 +1350,20 @@ let
       url = "mirror://cpan/authors/id/C/CH/CHANSEN/Authen-Simple-0.5.tar.gz";
       hash = "sha256-As3atH+L8aHL1Mm/jSWPbQURFJnDP4MV5yRIEvcmE6o=";
     };
+    # Our C crypt() doesn't support this weak "crypt" algorithm anymore.
+    postPatch = ''
+      patch -p1 <<-EOF
+        --- a/t/09password.t
+        +++ b/t/09password.t
+        @@ -10 +10 @@
+        -use Test::More tests => 16;
+        +use Test::More tests => 14;
+        @@ -14 +13,0 @@
+        -    [ 'crypt',     'lk9Mh5KHGjAaM',                          'crypt'        ],
+        @@ -18 +16,0 @@
+        -    [ 'crypt',     '{CRYPT}lk9Mh5KHGjAaM',                   '{CRYPT}'      ],
+      EOF
+    '';
     propagatedBuildInputs = [ ClassAccessor ClassDataInheritable CryptPasswdMD5 ParamsValidate ];
     meta = {
       description = "Simple Authentication";