{"id":"CVE-2016-4020","details":"The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS administrators to obtain sensitive information from host stack memory by accessing the Task Priority Register (TPR).","modified":"2026-04-16T01:39:31.498245835Z","published":"2016-05-25T15:59:04.927Z","related":["SUSE-SU-2016:1560-1","SUSE-SU-2016:1698-1","SUSE-SU-2016:1703-1","SUSE-SU-2016:1785-1","SUSE-SU-2016:2093-1","SUSE-SU-2016:2100-1","SUSE-SU-2016:2533-1","openSUSE-SU-2024:10233-1","openSUSE-SU-2024:10285-1"],"database_specific":{"unresolved_ranges":[{"cpe":"cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"10"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:a:redhat:openstack:11:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"11"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"8"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"9"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*","extracted_events":[{"last_affected":"12.04"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*","extracted_events":[{"last_affected":"14.04"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"15.10"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*","extracted_events":[{"last_affected":"16.04"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_eus:7.4:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.4"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_eus:7.5:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.5"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_eus:7.6:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.6"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_eus:7.7:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.7"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.4"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.6"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.7"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.6"}],"source":"CPE_FIELD"},{"cpe":"cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*","extracted_events":[{"last_affected":"7.7"}],"source":"CPE_FIELD"}]},"references":[{"type":"WEB","url":"http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0"},{"type":"ADVISORY","url":"http://www.securityfocus.com/bid/86067"},{"type":"ADVISORY","url":"http://www.ubuntu.com/usn/USN-2974-1"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2017:1856"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2017:2392"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2017:2408"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html"},{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/201609-01"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1313686"},{"type":"FIX","url":"https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html"},{"type":"FIX","url":"https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/qemu/qemu","events":[{"introduced":"0"},{"last_affected":"529d45e151d82a772cd9b9af64bb25f88fba6567"},{"last_affected":"c1eb2ddf0f8075faddc5f7c3d39feae3e8e9d6b4"},{"last_affected":"609d7596524ab204ccd71ef42c9eee4c7c338ea4"},{"last_affected":"823a3f11fb8f04c3c3cc0f95f968fef1bfc6534f"},{"last_affected":"131b9a05705636086699df15d4a6d328bb2585e8"}],"database_specific":{"cpe":["cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*","cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*","cpe:2.3:a:redhat:openstack:6.0:*:*:*:*:*:*:*","cpe:2.3:a:redhat:openstack:7.0:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*","cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*","cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"0"},{"last_affected":"2.6.2"},{"last_affected":"8.0"},{"last_affected":"6.0"},{"last_affected":"7.0"},{"last_affected":"4.0"}],"source":"CPE_FIELD"}}],"versions":["v0.1.0","v0.1.1","v0.1.3","v0.1.4","v0.1.5","v0.1.6","v0.11.0-rc0","v0.12.0-rc0","v0.13.0-rc0","v0.14.0-rc0","v0.2.0","v0.3.0","v0.4.0","v0.4.1","v0.4.2","v0.4.3","v0.4.4","v0.5.0","v1.0","v1.0-rc0","v1.0-rc1","v1.0-rc2","v1.0-rc3","v1.0-rc4","v1.1-rc0","v1.1-rc1","v1.1-rc2","v1.1.0","v1.1.0-rc2","v1.1.0-rc3","v1.1.0-rc4","v1.2.0","v1.2.0-rc0","v1.2.0-rc1","v1.2.0-rc2","v1.2.0-rc3","v1.3.0","v1.3.0-rc0","v1.3.0-rc1","v1.3.0-rc2","v1.4.0","v1.4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