[5289] in bugtraq
Java/JavaScript DoS
daemon@ATHENA.MIT.EDU (Ian McKellar)
Wed Sep 17 13:01:29 1997
Date: Wed, 17 Sep 1997 14:17:29 +0800
Reply-To: Ian McKellar <ian@HARVESTROAD.COM.AU>
From: Ian McKellar <ian@HARVESTROAD.COM.AU>
To: BUGTRAQ@NETSPACE.ORG
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Hi,
I was reading through my friendly `Webmaster in a Nutshell' O'Reilly book, and
I came across a reference to the creation of Java objects from JavaScript
i.e.:
<SCRIPT LANG=JavaScript>
var s=java.lang.System;
s.out.println("this is a test");
// or even
var r=new java.lang.String("this is a string");
</SCRIPT>
This intreaged me, so my mind turned (as it does) to matters of security. One
think you can't do with these dynamically created Java objects is make any
outbound network connections, or successfully receive and incoming connections.
One concerning thing you can do is:
javascript:while(true) { (new java.awt.Frame("DoS!")).show(); }
This will very quickly open lots of windows you can't close.
I don't see these as serious issues, but something that we should be aware of.
Ian
--
Ian McKellar imckellar@harvestroad.com.au
Web Author Phone: +61 8 9389 6200
Harvest Road Communications Fax: +61 8 9389 6201
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Copyright (c) 1997 Ian McKellar, All Rights Reserved. Publication or
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