RE: When GET = POST?

[Glyn Geoghegan <glyn.geoghegan () corsaire com>]

Jeff Dafoe wrote:
> > I'm going to buck the trend here, and say that from the 
> point of view 
> > of the script processing the form data, I don't think it 
> matters that 
> > much.
>
>     I am glad someone else feels the way I do about this 
> issue.  In the case of a web application, it's not important 
> to the script which method was used to submit the data as 
> long as proper validation and sanitization is performed.  All 
> that you really need to know is that the data originated from 
> an untrusted source and should be checked accordingly.  I 
> could see where explicitly checking for POST could lull 
> someone into a false sense of security.  Logging aside, 
> POSTed data is no safer than data sent via GET, so there is 
> no point in checking to see which method was used to submit the data.
>
> Jeff
Hi,

It is worth noting that 'practical' CSS attacks often rely on a GET request
to a vulnerable site, including abuse of back-end processing of an expected
POST.  These are, for example, executed through a social-engineering
email/website with a customised link containing the CSS attack.  

AFAIK *this* form of CSS attack is only possible through a GET request, so
its worth designing the apps to receive over POSTS, and to enforce that.


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