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The final version of the CSI 6.0 has been released. 
Find out why this is not just another Patch Management solution: http://secunia.com/blog/325/

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TITLE:
Xen "xen_failsafe_callback()" IRET Handling Denial of Service
Weakness

SECUNIA ADVISORY ID:
SA51834

VERIFY ADVISORY:
Secunia.com
http://secunia.com/advisories/51834/
Customer Area (Credentials Required)
https://ca.secunia.com/?page=viewadvisory&vuln_id=51834

RELEASE DATE:
2013-01-16

DISCUSS ADVISORY:
http://secunia.com/advisories/51834/#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/51834/

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=51834

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 error within
"xen_failsafe_callback()" when handling a failed IRET (Interrupt
Return) and can be exploited to cause a crash.

Successful exploitation requires that a ParaVirtual OPerationS
(PVOPS) guest is used.

SOLUTION:
Apply patch.

PROVIDED AND/OR DISCOVERED BY:
Reported by the vendor.

ORIGINAL ADVISORY:
XSA-40:
http://www.openwall.com/lists/oss-security/2013/01/16/6

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/

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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.

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Please Note:
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Secunia NEVER sends attached files with advisories.
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use those supplied by the vendor.

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