{"id":"DEBIAN-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":"2026-04-28T20:15:28.048957Z","published":"2016-05-25T15:59:04.927Z","upstream":["CVE-2016-4020"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2016-4020"}],"affected":[{"package":{"name":"qemu","ecosystem":"Debian:11","purl":"pkg:deb/debian/qemu?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.6+dfsg-2"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2016-4020.json"}},{"package":{"name":"qemu","ecosystem":"Debian:12","purl":"pkg:deb/debian/qemu?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.6+dfsg-2"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2016-4020.json"}},{"package":{"name":"qemu","ecosystem":"Debian:13","purl":"pkg:deb/debian/qemu?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.6+dfsg-2"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2016-4020.json"}},{"package":{"name":"qemu","ecosystem":"Debian:14","purl":"pkg:deb/debian/qemu?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.6+dfsg-2"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2016-4020.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N"}]}