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Gentoo Linux Security Advisory GLSA 201703-07 |
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https://security.gentoo.org/ |
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Severity: Normal |
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Title: Xen: Privilege Escalation |
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Date: March 28, 2017 |
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Bugs: #609120 |
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ID: 201703-07 |
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Synopsis |
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======== |
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|
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A vulnerability in Xen's bundled QEMU version might allow privilege |
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escalation. |
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Background |
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========== |
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|
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Xen is a bare-metal hypervisor. |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 app-emulation/xen-tools < 4.7.1-r8 >= 4.7.1-r8 |
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|
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Description |
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=========== |
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|
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In CIRRUS_BLTMODE_MEMSYSSRC mode the bitblit copy routine |
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cirrus_bitblt_cputovideo fails to check wethehr the specified memory |
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region is safe. |
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Impact |
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====== |
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|
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A local attacker could potentially execute arbitrary code with |
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privileges of Xen (QEMU) process on the host, gain privileges on the |
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host system, or cause a Denial of Service condition. |
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|
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Workaround |
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========== |
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|
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Running guests in Paravirtualization (PV) mode, or running guests in |
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Hardware-assisted virtualizion (HVM) utilizing stub domains mitigate |
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the issue. |
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Running HVM guests with the device model in a stubdomain will mitigate |
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the issue. |
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Changing the video card emulation to stdvga (stdvga=1, vga="stdvga", in |
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the xl domain configuration) will avoid the vulnerability. |
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Resolution |
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========== |
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All Xen Tools users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot -v ">=app-emulation/xen-tools-4.7.1-r8" |
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|
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References |
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========== |
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[ 1 ] CVE-2017-2620 |
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http://nvd.nist.gov/nvd.cfm?cvename=CVE-2017-2620 |
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Availability |
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============ |
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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https://security.gentoo.org/glsa/201703-07 |
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users' machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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https://bugs.gentoo.org. |
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License |
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======= |
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Copyright 2017 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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http://creativecommons.org/licenses/by-sa/2.5 |
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