ZDI-09-039: Microsoft Internet Explorer onreadystatechange Memory Corruption Vulnerability http://www.zerodayinitiative.com/advisories/ZDI-09-039 June 10, 2009 -- CVE ID: CVE-2009-1531 -- Affected Vendors: Microsoft -- Affected Products: Microsoft Internet Explorer 7 -- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Internet Explorer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page. The specific flaw exists when repeated calls are made to getElementsByTagName() and the reordering of the elements in the document causes an object to be allocated. The use of the event "onreadystatechange" during this operation improperly frees the previously allocated resource. The combination, with repeated page rendering, leads to the exploitable memory corruption. -- Vendor Response: Microsoft has issued an update to correct this vulnerability. More details can be found at: http://www.microsoft.com/technet/security/bulletin/MS09-019.mspx -- Disclosure Timeline: 2009-01-26 - Vulnerability reported to vendor 2009-06-10 - Coordinated public release of advisory -- Credit: This vulnerability was discovered by: * ling&wushi of team509 -- About the Zero Day Initiative (ZDI): Established by TippingPoint, The Zero Day Initiative (ZDI) represents a best-of-breed model for rewarding security researchers for responsibly disclosing discovered vulnerabilities. Researchers interested in getting paid for their security research through the ZDI can find more information and sign-up at: http://www.zerodayinitiative.com The ZDI is unique in how the acquired vulnerability information is used. TippingPoint does not re-sell the vulnerability details or any exploit code. Instead, upon notifying the affected product vendor, TippingPoint provides its customers with zero day protection through its intrusion prevention technology. Explicit details regarding the specifics of the vulnerability are not exposed to any parties until an official vendor patch is publicly available. Furthermore, with the altruistic aim of helping to secure a broader user base, TippingPoint provides this vulnerability information confidentially to security vendors (including competitors) who have a vulnerability protection or mitigation product. Our vulnerability disclosure policy is available online at: http://www.zerodayinitiative.com/advisories/disclosure_policy/
