ZDI-08-044: Mozilla Firefox CSSValue Array Memory Corruption Vulnerability


ZDI-08-044: Mozilla Firefox CSSValue Array Memory Corruption Vulnerability http://www.zerodayinitiative.com/advisories/ZDI-08-044 July 17, 2008 -- CVE ID: CVE-2008-2785 -- Affected Vendors: Mozilla Firefox -- Affected Products: Mozilla Firefox 2.0.x Mozilla Firefox 3.0.x -- TippingPoint(TM) IPS Customer Protection: TippingPoint IPS customers have been protected against this vulnerability by Digital Vaccine protection filter ID 6204. For further product information on the TippingPoint IPS, visit: http://www.tippingpoint.com -- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Mozilla Firefox. User interaction is required to exploit this vulnerability in that the target must visit a malicious page. The specific flaw exists in the browser's handling reference counters to the nsCSSValue:Array class. Creating more then 65,535 references will overflow a 16-bit reference counter and therefore result in an erroneous free() while the object still exists. Properly manipulated this can result in arbitrary code execution under the context of the current user. -- Vendor Response: Mozilla Firefox has issued an update to correct this vulnerability. More details can be found at: http://www.mozilla.org/security/announce/2008/mfsa2008-34.html -- Disclosure Timeline: 2008-06-17 - Vulnerability reported to vendor 2008-07-17 - Coordinated public release of advisory -- Credit: This vulnerability was discovered by: * Anonymous -- 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/ 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@3com.com.