( . ) `) ( . ' . ' `. ( , ) (, . `.' ) ('. ', ). , ('. ( ) ( (_,) .`), ) _ _, / _____/ / _ \ ____ ____ _____ \____ \==/ /_\ \ _/ ___\/ _ \ / \ / \/ | \\ \__( <_> ) Y Y \ /______ /\___|__ / \___ >____/|__|_| / \/ \/ .-. \/ \/:wq (x.0) '=.|w|.=' _='`"``=. presents.. Microsoft Internet Explorer textNode Use-After-Free PDF: http://security-assessment.com/files/documents/advisory/ms13_037_ie_textnode_uaf.pdf Metasploit: http://www.security-assessment.com/files/documents/advisory/ms13_037_ie_textnode_uaf.rb +-----------+ |Description| +-----------+ A Use-after-free memory corruption vulnerability was identified in Microsoft Internet Explorer 8. This allows a malicious user to remotely execute arbitrary code on a vulnerable user’s machine, in the context of the current user. The memory corruption happens when the application of a style sheet performs style computations on the DOM. A DOM textNode pointer becomes corrupted after the style computation. This pointer is then overwritten when the innerHTML property on the parent object is set. +------------+ |Exploitation| +------------+ Exploitation of this vulnerability requires a user to visit a page containing specially crafted JavaScript. Users can generally be lured to visit web pages via email, instant message or links on the internet. Vulnerabilities like this are often hosted on legitimate websites which have been compromised by other means. Exploitation of this vulnerability is relatively simple. Under correct conditions, setting the innerHTML of the object results in an attacker controlled direct pointer overwrite. The only obstacle is having to perform heap manipulation before a ROP chain can be used. +--------+ |Solution| +--------+ Microsoft validated this security issue in Internet Explorer 8 and issued a patch (MS13-037) to remedy it. Security-Assessment.com recommends applying the patch which has been made available via Windows Update. +-----------------------------+ |About Security-Assessment.com| +-----------------------------+ Security-Assessment.com is a leading team of Information Security consultants specialising in providing high quality Information Security services to clients throughout the Asia Pacific region. Our clients include some of the largest globally recognised companies in areas such as finance, telecommunications, broadcasting, legal and government. Our aim is to provide the very best independent advice and a high level of technical expertise while creating long and lasting professional relationships with our clients. Security-Assessment.com is committed to security research and development, and its team continues to identify and responsibly publish vulnerabilities in public and private software vendor's products. Members of the Security-Assessment.com R&D team are globally recognised through their release of whitepapers and presentations related to new security research. For further information on this issue or any of our service offerings, contact us: Web www.security-assessment.com Email info@security-assessment.com