Bug 1160643 (CVE-2014-8595, xsa110)

Summary:	CVE-2014-8595 kernel: xen: Missing privilege level checks in x86 emulation of far branches (xsa110)
Product:	[Other] Security Response	Reporter:	Petr Matousek <pmatouse>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	drjones, imammedo, pbonzini, rkrcmar, security-response-team, vkuznets
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-11-05 10:14:48 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1165204
Bug Blocks:	1160648

Description Petr Matousek 2014-11-05 10:11:49 UTC

The emulation of far branch instructions (CALL, JMP, and RETF in Intel
assembly syntax, LCALL, LJMP, and LRET in AT&T assembly syntax)
incompletely performs privilege checks.

Malicious HVM guest user mode code may be able to elevate its
privileges to guest supervisor mode, or to crash the guest.

Acknowledgements:

Red Hat would like to thank the Xen for reporting this issue.

Comment 3 Petr Matousek 2014-11-05 10:14:48 UTC

Statement:

Not vulnerable.

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

Comment 4 Vincent Danen 2014-11-18 14:44:42 UTC

External References:

http://xenbits.xen.org/xsa/advisory-110.html

Comment 5 Vincent Danen 2014-11-18 14:45:41 UTC

Created xen tracking bugs for this issue:

Affects: fedora-all [bug 1165204]