Xen.org security team
2013-Jan-22 12:02 UTC
Xen Security Advisory 35 (CVE-2013-0152) - Nested HVM exposes host to being driven out of memory by guest
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Xen Security Advisory CVE-2013-0152 / XSA-35
version 3
Nested HVM exposes host to being driven out of memory by guest
UPDATES IN VERSION 3
===================
Public release.
ISSUE DESCRIPTION
================
Guests are currently permitted to enable nested virtualization on
themselves. Missing error handling cleanup in the handling code makes
it possible for a guest, particularly a multi-vCPU one, to repeatedly
invoke this operation, thus causing a leak of - over time - unbounded
amounts of memory.
IMPACT
=====
A malicious domain can mount a denial of service attack affecting the
whole system.
VULNERABLE SYSTEMS
=================
Only Xen 4.2 and Xen unstable are vulnerable. Xen 4.1 and earlier are
not vulnerable.
The vulnerability is only exposed by HVM guests.
MITIGATION
=========
Running only PV guests will avoid this vulnerability.
RESOLUTION
=========
Applying the appropriate attached patch resolves this issue.
To fix both XSA 34 and XSA 35, first apply xsa34-4.2.patch from XSA 34
and then *also* apply xsa35-4.2-with-xsa34.patch from this advisory.
To fix this issue without addressing XSA 34, use xsa35.patch.
$ sha256sum xsa35*.patch
8372322e986bc2210f0d35b4d35a029301bd28fc1dffb789dff1436eb2024723
xsa35-4.2-with-xsa34.patch
e69b01033b0fa4c3d175697566d2f0b161337e8d206654919937f77721dbf866 xsa35.patch
$
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Xen.org security team
2013-Jan-23 18:29 UTC
Xen Security Advisory 35 (CVE-2013-0152) - Nested HVM exposes host to being driven out of memory by guest
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Hash: SHA1
Xen Security Advisory CVE-2013-0152 / XSA-35
version 4
Nested HVM exposes host to being driven out of memory by guest
UPDATES IN VERSION 4
===================
Fix corrupt patch xsa35-4.2-with-xsa34.patch.
ISSUE DESCRIPTION
================
Guests are currently permitted to enable nested virtualization on
themselves. Missing error handling cleanup in the handling code makes
it possible for a guest, particularly a multi-vCPU one, to repeatedly
invoke this operation, thus causing a leak of - over time - unbounded
amounts of memory.
IMPACT
=====
A malicious domain can mount a denial of service attack affecting the
whole system.
VULNERABLE SYSTEMS
=================
Only Xen 4.2 and Xen unstable are vulnerable. Xen 4.1 and earlier are
not vulnerable.
The vulnerability is only exposed by HVM guests.
MITIGATION
=========
Running only PV guests will avoid this vulnerability.
RESOLUTION
=========
Applying the appropriate attached patch resolves this issue.
To fix both XSA 34 and XSA 35, first apply xsa34-4.2.patch from XSA 34
and then *also* apply xsa35-4.2-with-xsa34.patch from this advisory.
To fix this issue without addressing XSA 34, use xsa35.patch.
$ sha256sum xsa35*.patch
4a103bf14dd060f702289db539a8c6c69496bdfd1de5d0c0468c3aab7b34f6a5
xsa35-4.2-with-xsa34.patch
e69b01033b0fa4c3d175697566d2f0b161337e8d206654919937f77721dbf866 xsa35.patch
$
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