ZDI-07-070: Skype skype4com URI Handler Remote Heap Corruption Vulnerability http://www.zerodayinitiative.com/advisories/ZDI-07-070.html December 6, 2007 -- CVE ID: CVE-2007-5989 -- Affected Vendor: Skype -- Affected Products: Skype < 3.6 GOLD -- TippingPoint(TM) IPS Customer Protection: TippingPoint IPS customers have been protected against this vulnerability by Digital Vaccine protection filter ID 5752. For further product information on the TippingPoint IPS: http://www.tippingpoint.com -- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Skype. User interaction is required to exploit this vulnerability in that the target must visit a malicious page. The specific flaw exists within the 'skype4com' URI handler created by Skype during installation. When processing short string values through this handler an exploitable memory corruption may occur which can result in arbitrary code execution under the context of the current user. -- Vendor Response: Skype has corrected this issue as of 11/15/2007. All clients updated or installed as of that date are patched to this issue. -- Disclosure Timeline: 2007.11.02 - Vulnerability reported to vendor 2007.12.06 - Coordinated public release of advisory -- Credit: This vulnerability was discovered by an anonymous researcher. -- 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. 3Com does not re-sell the vulnerability details or any exploit code. Instead, upon notifying the affected product vendor, 3Com 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, 3Com provides this vulnerability information confidentially to security vendors (including competitors) who have a vulnerability protection or mitigation product. CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is being sent by 3Com for the sole use of the intended recipient(s) and may contain confidential, proprietary and/or privileged information. Any unauthorized review, use, disclosure and/or distribution by any recipient is prohibited. If you are not the intended recipient, please delete and/or destroy all copies of this message regardless of form and any included attachments and notify 3Com immediately by contacting the sender via reply e-mail or forwarding to 3Com at postmaster (at) 3com (dot) com. [email concealed]