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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 Two Nested Virtualization Denial of Service Vulnerabilities

SECUNIA ADVISORY ID:
SA51874

VERIFY ADVISORY:
Secunia.com
http://secunia.com/advisories/51874/
Customer Area (Credentials Required)
https://ca.secunia.com/?page=viewadvisory&vuln_id=51874

RELEASE DATE:
2013-01-22

DISCUSS ADVISORY:
http://secunia.com/advisories/51874/#comments

AVAILABLE ON SITE AND IN CUSTOMER AREA:
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 * Criticality Level
 * Impact
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 * Operating System / Software
 * CVE Reference(s)

http://secunia.com/advisories/51874/

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https://ca.secunia.com/?page=viewadvisory&vuln_id=51874

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:
Two vulnerabilities have been reported in Xen, which can be exploited
by malicious, local users in a guest virtual machine to cause a DoS
(Denial of Service).

1) An error when mapping guest pages while handling nested
virtualization can be exploited to exhaust the transient mapping
slots and cause a crash.

Successful exploitation of this vulnerability requires 32-bit
hypervisors running fully virtualized (HVM) guests on Intel or AMD.

2) A memory leak error within the error handling mechanism when guest
virtual machines enable nested virtualization on themselves can be
exploited to exhaust memory and render the system unusable.

Successful exploitation of this vulnerability requires running fully
virtualized (HVM) guests.

The vulnerability is reported in versions 4.2.x.

SOLUTION:
Apply patches xsa34-4.2.patch and xsa35.patch.

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

ORIGINAL ADVISORY:
XSA-34, XSA-35:
http://www.openwall.com/lists/oss-security/2013/01/22/10
http://www.openwall.com/lists/oss-security/2013/01/22/9

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:
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private users keeping their systems up to date against the latest
vulnerabilities.

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use those supplied by the vendor.

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