Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 28 Oct 2009 11:38:16 +0100
From: Marcus Meissner <meissner@...e.de>
To: oss-security@...ts.openwall.com
Subject: Re: Handling cases of CWE-776

On Wed, Oct 28, 2009 at 12:02:40AM +0000, Tim Brown wrote:
> All,
> 
> How are problems with XML bombs (the so called "billion laughs" attack) being 
> handled?  Should I be filing such bugs against the applications that exposes 
> the XML parser to user input or is it better to report the issue against the 
> parser themselves.  For example, the test case I've prepared for one affected 
> parser simply causes the CPU to spin but the system appears to stay 
> responsive (so far ;)).  Is it even fair to call such a denial of service? 
> (If the code was executed in a real application, no further processing would 
> happen within the affected process as the parser is tied up in memmove()s).  
> I'm just curious as I don't want to waste peoples time with the disclosure 
> process if others are simply filing "standard" bugs against affected parsers 
> and moving on to more interesting matters.

If an application can be made unresponsive this way it would still be
a denial of service against this app, so Yes.

It always should however be checked if the application can get this data
from a real life attacker or if a admin user needs to push it in. For the
latter it is not DoS in my eyes.

Ciao, Marcus

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.