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Jelmer
14/10/04, 03:25
Adobe acrobat / Adobe Reader 6 can read local files

Description

Acrobat/ Acrobat reader is software for viewing and printing Adobe Portable
Document Format (PDF) files. Adobe PDF files can be viewed on most major
operating systems.

Version 6 of this program has an issue with the way it handles embedding
macromedia flash files directly into a pdf. This allows a malicious website
operator to steal local files from a user's hard drive including cookie
files

Technical Details:

Version 6 of the pdf format introduced a new way to embed movies directly
into the pdf file. In previous versions one could only link to media in
external files

Adobe reader extracts this swf file from the pdf and saves it under a random
name to your temp dir, on windows XP and 2000 this dir is usually located at

C:\Documents and Settings\<username>\Local Settings\Temp

It then appears to "link" directly to this saved file in effect making your
local hard disk the codebase for this swf file and allowing it read access
to all of the files on your hard drive

Systems affected:

Adobe reader 6
Adobe acrobat 6

Demonstration:

Create a text file called c:\jelmer.txt then proceed to click on

http://62.131.86.111/security/acrobat/demo.pdf

Risk: medium

Nick Leoncavallo
15/10/04, 01:15
In-Reply-To: <0I5H001195EBYO@smtp13.wxs.nl>

This can be defeated by disallowing multimedia operations in the "Trust Manager" settings.

I'm not sure I want to the other setting labeled "Allow documents to open other files and launch other applications" either, but it doesn't have an affect on Jelmer's example.

- Nick

>
>Adobe acrobat / Adobe Reader 6 can read local files
>
>Description
>
>Acrobat/ Acrobat reader is software for viewing and printing Adobe Portable
>Document Format (PDF) files. Adobe PDF files can be viewed on most major
>operating systems.
>
>Version 6 of this program has an issue with the way it handles embedding
>macromedia flash files directly into a pdf. This allows a malicious website
>operator to steal local files from a user's hard drive including cookie
>files
>
>Technical Details:
>
>Version 6 of the pdf format introduced a new way to embed movies directly
>into the pdf file. In previous versions one could only link to media in
>external files
>
>Adobe reader extracts this swf file from the pdf and saves it under a random
>name to your temp dir, on windows XP and 2000 this dir is usually located at
>
>C:\Documents and Settings\<username>\Local Settings\Temp
>
>It then appears to "link" directly to this saved file in effect making your
>local hard disk the codebase for this swf file and allowing it read access
>to all of the files on your hard drive
>
>Systems affected:
>
>Adobe reader 6
>Adobe acrobat 6
>
>Demonstration:
>
>Create a text file called c:\jelmer.txt then proceed to click on
>
>http://62.131.86.111/security/acrobat/demo.pdf
>
>Risk: medium
>
>
>

Shannon Eric Peevey
18/10/04, 20:05
Quoting Nick Leoncavallo <nleoncavallo@yahoo.com>:

> In-Reply-To: <0I5H001195EBYO@smtp13.wxs.nl>
>
> This can be defeated by disallowing multimedia operations in the
> "Trust Manager" settings.
>
This setting only blocks the problem if the user is using IE...

--
Shannon Eric Peevey
President - EriKin Corporation
speeves@erikin.com
(940) 391-6777
http://www.erikin.com

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