diff --git a/tests/scripts/test-ref-configs.pl b/tests/scripts/test-ref-configs.pl
index bd11c09..1e65969 100755
--- a/tests/scripts/test-ref-configs.pl
+++ b/tests/scripts/test-ref-configs.pl
@@ -50,6 +50,15 @@
     exit 1;
 }
 
+# Create a seedfile for configurations that enable MBEDTLS_ENTROPY_NV_SEED.
+# For test purposes, this doesn't have to be cryptographically random.
+if (!-e "tests/seedfile" || -s "tests/seedfile" < 64) {
+    local *SEEDFILE;
+    open SEEDFILE, ">tests/seedfile" or die;
+    print SEEDFILE "*" x 64 or die;
+    close SEEDFILE or die;
+}
+
 while( my ($conf, $data) = each %configs ) {
     system( "cp $config_h.bak $config_h" ) and die;
     system( "make clean" ) and die;