So I think your idea was partly good, the 301 redirection will knock off
the URL fragment, but it has nothing to do with GET vs POST, and you'll
need to redirect it to a unique token to prevent infinite loops or
someone just forwarding to a guessable token.
> Why bother with the token handling? If the request URI is a PDF and it is a
> POST or contains URL parameters, just 30x to the naked PDF. Otherwise it's
> safe to serve.
>
> -j
>
> On 1/3/07, Amit Klein <aksecurity (at) gmail (dot) com [email concealed]> wrote:
>>
>> Amit Klein wrote:
>> > pdp (architect) wrote:
>> >> I will be very quick and just point to links where you can read about
>> >> this issue.
>> >>
>> >> It seams that PDF documents can execute JavaScript code for no
>> >> apparent reason by using the following template:
>> >>
>> >>
>> >>
>> http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_
here
>> >>
>> >>
>> >> You must understand that the attacker doesn't need to have write
>> >> access to the specified PDF document. In order to get an XSS vector
>> >> working you need to have a PDF file hosted on the target and that's
>> >> all about it. The rest is just a matter of your abilities and desires.
It's not a part of the URL string that is passed to the header:
http://www.google.com/appliance/pdf/google_gsa_datasheet.pdf#blah=javasc
ript:alert(%22XSS%22);
becomes:
GET /appliance/pdf/google_gsa_datasheet.pdf HTTP/1.0
Host: www.google.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1
Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plai
n;q=0.8,image/png,*/*;q=0.5
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Proxy-Connection: keep-alive
Pragma: no-cache
So I think your idea was partly good, the 301 redirection will knock off
the URL fragment, but it has nothing to do with GET vs POST, and you'll
need to redirect it to a unique token to prevent infinite loops or
someone just forwarding to a guessable token.
-RSnake
http://ha.ckers.org/
http://sla.ckers.org/
http://ha.ckers.org/fierce/
On Wed, 3 Jan 2007, James Landis wrote:
> Why bother with the token handling? If the request URI is a PDF and it is a
> POST or contains URL parameters, just 30x to the naked PDF. Otherwise it's
> safe to serve.
>
> -j
>
> On 1/3/07, Amit Klein <aksecurity (at) gmail (dot) com [email concealed]> wrote:
>>
>> Amit Klein wrote:
>> > pdp (architect) wrote:
>> >> I will be very quick and just point to links where you can read about
>> >> this issue.
>> >>
>> >> It seams that PDF documents can execute JavaScript code for no
>> >> apparent reason by using the following template:
>> >>
>> >>
>> >>
>> http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_
here
>> >>
>> >>
>> >> You must understand that the attacker doesn't need to have write
>> >> access to the specified PDF document. In order to get an XSS vector
>> >> working you need to have a PDF file hosted on the target and that's
>> >> all about it. The rest is just a matter of your abilities and desires.
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