--- a/src/java.base/share/classes/com/sun/crypto/provider/PBEKey.java	Thu Aug 23 10:52:27 2018 +0200
+++ b/src/java.base/share/classes/com/sun/crypto/provider/PBEKey.java	Thu Aug 23 11:37:14 2018 +0100
@@ -73,7 +73,7 @@
         this.key = new byte[passwd.length];
         for (int i=0; i<passwd.length; i++)
             this.key[i] = (byte) (passwd[i] & 0x7f);
-        Arrays.fill(passwd, ' ');
+        Arrays.fill(passwd, '\0');
         type = keytype;
 
         // Use the cleaner to zero the key when no longer referenced