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AL-2006.0051 -- [Win] -- Microsoft Hyperlink Object Library stack buffer overflow

Date: 23 June 2006
References: AU-2006.0021  ESB-2006.0564  

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A  U  S  C  E  R  T                                           A  L  E  R  T

                       AL-2006.0051 -- AUSCERT ALERT
         Microsoft Hyperlink Object Library stack buffer overflow
                               23 June 2006


        AusCERT Alert Summary

Product:              Microsoft Windows
                      Applications using HLINK.DLL to handle hyperlinks
Publisher:            US-CERT
Impact:               Execute Arbitrary Code/Commands
Access:               Remote/Unauthenticated
CVE Names:            CVE-2006-3086

Ref:                  AU-2006.0021

Original Bulletin:

Comment: This advisory provides further information on the vulnerability
         reported in AU-2006-0021.
         Currently Microsoft Office applications are confirmed as using
         the vulnerable component. Other software may also be affected.
         Exploit code for this vulnerability is publicly available.
         No official advisory or fix is available from Microsoft at
         this point.

- --------------------------BEGIN INCLUDED TEXT--------------------

US-CERT Vulnerability Note VU#394444
Microsoft Hyperlink Object Library stack buffer overflow


	The Microsoft Windows system library for handling hyperlinks contains
	a buffer overflow. Exploitation of this vulnerability may allow an
	attacker to execute arbitrary code.

I. Description

	Microsoft Hyperlink Object Library (HLINK.DLL)

	The Hyperlink Object Library provides interfaces for handling
	hyperlinks. More information is available in the Microsoft Hyperlinks

The Problem

	There is a stack-based buffer overflow in the Microsoft Hyperlink
	Object Library. The overflow may be triggered by clicking a specially
	crafted hyperlink. Note that any program that links to the HLINK.DLL
	library may be vulnerable, including Microsoft Office applications.

	Exploit code for this vulnerability is publicly available.

II. Impact

	By convincing a user to access a specially crafted hyperlink, an
	attacker could execute arbitrary code with the privileges of the
	attacked user. If the user is logged in with administrative privileges,
	the attacker could take complete control of a vulnerable system.

III. Solution

	There is currently no patch or update to correct this problem. Until
	a solution is available, refer to the workaround below.

	Do not follow unsolicited hyperlinks

	Do not click on unsolicited links received in email or embedded in
	Office documents. Exploitation of this vulnerability requires a user
	to click a specially crafted link. By only accessing hyperlinks from
	known and trusted sources, the chances of exploitation are reduced.

Systems Affected

	Vendor	Status	Date Updated
	Microsoft Corporation	Vulnerable	21-Jun-2006



	This vulnerability was reported by kcope.

	This document was written by Jeff Gennari.
	Other Information
	Date Public	06/18/2006
	Date First Published	06/21/2006 02:49:04 PM
	Date Last Updated	06/21/2006
	CERT Advisory	 
	CVE Name	CVE-2006-3086
	Metric	37.50
	Document Revision	53

- --------------------------END INCLUDED TEXT--------------------

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