Advisory ID: SYSS-2015-029
Product: Page2Flip
Vendor: w!ssenswerft GmbH
Affected Version(s): Premium App 2.5, probably also in Business App 
                     and Basic App, and in lower versions
Tested Version(s): Premium App 2.5
Vulnerability Type: Insecure Direct Object Reference (CWE-932)
Risk Level: Medium
Solution Status: Open
Vendor Notification: 2015-06-29
Solution Date: 
Public Disclosure: 
CVE Reference: Not yet assigned
Author of Advisory: Dr. Erlijn van Genuchten (SySS GmbH)

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Overview:

With the Page2Flip Web application, it is possible to create e-papers in
PDF format that can be flicked through digitally. Such e-papers can be
used for magazines, catalogues, flyers, etc. (see [1]).

The Page2Flip application allows preview content to be accessed by
unauthenticated users.

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Vulnerability Details:

The SySS GmbH identified a vulnerability in the "preview" functionality
of the Page2Flip application.

Pageflip preview content can be accessed by unauthenticated users if
a valid URL is known.

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Proof of Concept (PoC):

By knowing or guessing a valid URL for pageflip preview content, an
unauthenticated user can access this data.

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Solution:


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Disclosure Timeline:

2015-06-23: Vulnerability discovered
2015-06-29: Vulnerability reported to vendor
2015-07-07: Reported vulnerabilities again as the vendor did not respond 
            to the first e-mail
2015-07-14: Reminder sent concerning reported vulnerabilities
2015-08-24: Public release of security advisory according to the SySS
            Responsible Disclosure Policy

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References:

[1] Page2Flip homepage
    http://page2flip.de/
[2] SySS Responsible Disclosure Policy
    https://www.syss.de/en/news/responsible-disclosure-policy/

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Credits:

This security vulnerability was found by Dr. Erlijn van Genuchten of the
SySS GmbH.

E-Mail: erlijn.vangenuchten@syss.de
Public Key: https://www.syss.de/fileadmin/dokumente/Materialien/PGPKeys/Erlijn_vanGenuchten.asc
Key ID: 0xBD96FF2A
Key Fingerprint: 17BB 4CED 755A CBB3 2D47 C563 0CA5 8637 BD96 FF2A

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Disclaimer:

The information provided in this security advisory is provided "as is" 
and without warranty of any kind. Details of this security advisory may
be updated in order to provide as accurate information as possible. The
latest version of this security advisory is available on the SySS Web
site.

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Copyright:

Creative Commons - Attribution (by) - Version 3.0
URL: http://creativecommons.org/licenses/by/3.0/deed.en