---------------------------------------------------------------------- The Secunia CSI 5.0 Beta - now available for testing Find out more, take a free test drive, and share your opinion with us: http://secunia.com/blog/242 ---------------------------------------------------------------------- TITLE: Xen "__addr_ok()" Macro Input Validation Weakness SECUNIA ADVISORY ID: SA45835 VERIFY ADVISORY: Secunia.com http://secunia.com/advisories/45835/ Customer Area (Credentials Required) https://ca.secunia.com/?page=viewadvisory&vuln_id=45835 RELEASE DATE: 2011-09-06 DISCUSS ADVISORY: http://secunia.com/advisories/45835/#comments AVAILABLE ON SITE AND IN CUSTOMER AREA: * Last Update * Popularity * Comments * Criticality Level * Impact * Where * Solution Status * Operating System / Software * CVE Reference(s) http://secunia.com/advisories/45835/ ONLY AVAILABLE IN CUSTOMER AREA: * Authentication Level * Report Reliability * Secunia PoC * Secunia Analysis * Systems Affected * Approve Distribution * Remediation Status * Secunia CVSS Score * CVSS https://ca.secunia.com/?page=viewadvisory&vuln_id=45835 ONLY AVAILABLE WITH SECUNIA CSI AND SECUNIA PSI: * AUTOMATED SCANNING http://secunia.com/vulnerability_scanning/personal/ http://secunia.com/vulnerability_scanning/corporate/wsus_sccm_3rd_third_party_patching/ DESCRIPTION: A weakness has been reported in Xen, which can be exploited by malicious, local users in a guest virtual machine to cause a DoS (Denial of Service). The weakness is caused due to an input validation error within the "__addr_ok()" macro (xen/include/asm-x86/x86_64/uaccess.h) and can be exploited to crash the host system via malicious hypercalls. Successful exploitation requires administrative privileges within a 64bit PV guest. The weakness is reported in version 3.3. Prior versions may also be affected. SOLUTION: Apply the patch. See vendor's advisory for additional details. PROVIDED AND/OR DISCOVERED BY: Reported by the vendor. ORIGINAL ADVISORY: Xen XSA-4: http://www.openwall.com/lists/oss-security/2011/09/02/2 OTHER REFERENCES: Further details available in Customer Area: http://secunia.com/vulnerability_intelligence/ DEEP LINKS: Further details available in Customer Area: http://secunia.com/vulnerability_intelligence/ EXTENDED DESCRIPTION: Further details available in Customer Area: http://secunia.com/vulnerability_intelligence/ EXTENDED SOLUTION: Further details available in Customer Area: http://secunia.com/vulnerability_intelligence/ EXPLOIT: Further details available in Customer Area: http://secunia.com/vulnerability_intelligence/ ---------------------------------------------------------------------- About: This Advisory was delivered by Secunia as a free service to help private users keeping their systems up to date against the latest vulnerabilities. Subscribe: http://secunia.com/advisories/secunia_security_advisories/ Definitions: (Criticality, Where etc.) http://secunia.com/advisories/about_secunia_advisories/ Please Note: Secunia recommends that you verify all advisories you receive by clicking the link. Secunia NEVER sends attached files with advisories. Secunia does not advise people to install third party patches, only use those supplied by the vendor. ---------------------------------------------------------------------- Unsubscribe: Secunia Security Advisories http://secunia.com/sec_adv_unsubscribe/?email=packet%40packetstormsecurity.org ----------------------------------------------------------------------