Risk
12/22/2010
10:51 PM
George V. Hulme
George V. Hulme
Commentary
50%
50%

Microsoft Moves To Block Zero Day Attack

A French IT security firm recently warned of a new vulnerability that opens most versions of Microsoft Internet Explorer open to attack.

A French IT security firm recently warned of a new vulnerability that opens most versions of Microsoft Internet Explorer open to attack.Should a successful hack be launched, the attacker could circumvent many of the defenses available in both Windows Vista and Windows 7. The attacker could also run code of their choice on the target system.

To make the situation more pressing, the Metasploit project recently added an exploit to its database that successfully evades Microsoft's ASLR (Address Space Layout Randomization) and bypass DEP (Data Execution Prevention) defenses.

In an e-mail to InformationWeek, Microsoft noted that there is currently no indication that customers are being attacked. Late this evening, Microsoft's Security Research & Defense blog posted an update and mitigation guidance for the vulnerability.

Microsoft provided some details on the exploit:

The Metasploit project recently published an exploit for this vulnerability using a known technique to evade ASLR (Address Space Layout Randomization) and bypass DEP (Data Execution Prevention).

In a few words, Internet Explorer loads mscorie.dll, a library that was not compiled with /DYNAMICBASE (thus not supporting ASLR and being located always at the same base) when processing some html tags. Attackers use these predictable mappings to evade ASLR and bypass DEP by using ROP (return oriented programming) gadgets from these DLLs in order to allocate executable memory, copying their shellcode and jumping into it. Note that without that predictable mapping, the only public ways to evade ASLR and DEP is through:

• Use of this (in case the current vulnerability allows) or another vulnerability as an information leak.

• Using techniques such as JIT-spraying or similar ones. Please note IE only JITs IE9's javascript and there are security mitigations in place. But third party plugins could JIT in an insecure manner.

The same post recommends users employ Enhanced Mitigation Experience Toolkit (EMET) to block the threat. According to Microsoft, by using EMET, the associated mandatory ASLR, Heap Spray pre-allocation, and EAT Filtering will all mitigate the risk associated with this attack.

Microsoft also has more information in Security Advisory 2488013.

For my security and technology tweets throughout the day, find me on Twitter.

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2015-0702
Published: 2015-04-20
Unrestricted file upload vulnerability in the Custom Prompts upload implementation in Cisco Unified MeetingPlace 8.6(1.9) allows remote authenticated users to execute arbitrary code by using the languageShortName parameter to upload a file that provides shell access, aka Bug ID CSCus95712.

CVE-2015-0703
Published: 2015-04-20
Cross-site scripting (XSS) vulnerability in the administrative web interface in Cisco Unified MeetingPlace 8.6(1.9) allows remote attackers to inject arbitrary web script or HTML via unspecified vectors, aka Bug ID CSCus95857.

CVE-2015-1235
Published: 2015-04-19
The ContainerNode::parserRemoveChild function in core/dom/ContainerNode.cpp in the HTML parser in Blink, as used in Google Chrome before 42.0.2311.90, allows remote attackers to bypass the Same Origin Policy via a crafted HTML document with an IFRAME element.

CVE-2015-1236
Published: 2015-04-19
The MediaElementAudioSourceNode::process function in modules/webaudio/MediaElementAudioSourceNode.cpp in the Web Audio API implementation in Blink, as used in Google Chrome before 42.0.2311.90, allows remote attackers to bypass the Same Origin Policy and obtain sensitive audio sample values via a cr...

CVE-2015-1237
Published: 2015-04-19
Use-after-free vulnerability in the RenderFrameImpl::OnMessageReceived function in content/renderer/render_frame_impl.cc in Google Chrome before 42.0.2311.90 allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors that trigger renderer IPC messages ...

Dark Reading Radio
Archived Dark Reading Radio
Join security and risk expert John Pironti and Dark Reading Editor-in-Chief Tim Wilson for a live online discussion of the sea-changing shift in security strategy and the many ways it is affecting IT and business.