Bug 851165 (CVE-2012-3495)

Summary: CVE-2012-3495 kernel: xen: hypercall physdev_get_free_pirq vulnerability
Product: [Other] Security Response Reporter: Petr Matousek <pmatouse>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: drjones, lersek, pbonzini, security-response-team, tburke
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard: impact=moderate,public=20120905,reported=20120823,source=upstream,cvss2=5.5/AV:A/AC:L/Au:S/C:N/I:N/A:C,rhel-5/kernel-xen=notaffected,fedora-all/xen=affected
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On: 854589    
Bug Blocks: 851204    

Description Petr Matousek 2012-08-23 07:55:46 EDT
PHYSDEVOP_get_free_pirq does not check that its call to get_free_pirq succeeded, and if it fails will use the error code as an array index.

A malicious guest might be able to cause the host to crash, leading to a DoS, depending on the exact memory layout.  Privilege escalation is a theoretical possibility which cannot be ruled out, but is considered unlikely


Red Hat would like to thank the Xen project for reporting this issue. Upstream acknowledges Matthew Daley as the original reporter.
Comment 3 Petr Matousek 2012-08-23 07:57:31 EDT

Not vulnerable.

This issue did not affect the versions of the kernel-xen package as shipped with Red Hat Enterprise Linux 5.

This issue did not affect Red Hat Enterprise Linux 6 and Red Hat Enterprise MRG as we did not have support for Xen hypervisor.
Comment 4 Petr Matousek 2012-09-05 07:43:07 EDT
Now public via:

Comment 5 Petr Matousek 2012-09-05 07:44:35 EDT
Created xen tracking bugs for this issue

Affects: fedora-all [bug 854589]
Comment 6 Fedora Update System 2012-09-17 13:59:57 EDT
xen-4.1.3-2.fc16 has been pushed to the Fedora 16 stable repository.  If problems still persist, please make note of it in this bug report.