Check Point Software Technologies - Vulnerability Discovery Team (VDT) http://www.checkpoint.com/defense/ Internet Explorer Uninitialized Memory Corruption Vulnerability CVE-2010-3331 - MS10-071 INTRODUCTION There exists a vulnerability within the way internet explorer handles specific objects that has not been correctly initialized or has been deleted, which leads to uninitialized memory reference and code execution. This vulnerability can be triggered thru different vectors, been Microsoft Word one of the tested ones. This problem was confirmed in the following versions of Internet Explorer and Windows, other versions maybe also affected. Internet Explorer 6 running in All Versions of Windows Internet Explorer 7 running in All Versions of Windows Internet Explorer 8 running in All Versions of Windows MICROSOFT EXPLOTABILITY INDEX In order to help the Microsoft Response Team we did further analysis on the vulnerability and we classify it as: 1 consistent exploit code likely. Important to note again that since the faulty code also appears inside the mshtml.dll other applications may behave differently when triggering the problem (even more when talking about 3rd parties). CVSS Scoring System The CVSS score is: 8.3 Base Score: 10 Temporal Score: 8.3 We used the following values to calculate the scores: Base score is: AV:N/AC:L/Au:N/C:C/I:C/A:C Temporal score is: E:F/RL:OF/RC:C TRIGGERING THE PROBLEM This vulnerability can be triggered by creating a persistent object with class id: CLSID:AE24FDAE-03C6-11D1-8B76-0080C744F389. The problem is triggered by the an exploit code available to interested party which causes invalid memory access in all the referred versions. CREDITS This vulnerability was discovered and researched by Rodrigo Rubira Branco from Check Point Vulnerability Discovery Team (VDT). Best Regards, Rodrigo. -- Rodrigo Rubira Branco Senior Security Researcher Vulnerability Discovery Team (VDT) Check Point Software Technologies