CVE-2016-4020
Status: ModifiedMedium (6.5)—
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).
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
- Base score: 6.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.37%
- Percentile among all scored CVEs: 29
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (11)
Canonical — Ubuntu LinuxDebian — Debian LinuxQemu — QemuRedhat — Enterprise Linux DesktopRedhat — Enterprise Linux EUSRedhat — Enterprise Linux ServerRedhat — Enterprise Linux Server AUSRedhat — Enterprise Linux Server TUSRedhat — Enterprise Linux WorkstationRedhat — OpenstackRedhat — Virtualization
CWEs
- NVD-CWE-noinfo
References
- http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0
- http://www.securityfocus.com/bid/86067
- http://www.ubuntu.com/usn/USN-2974-1
- https://access.redhat.com/errata/RHSA-2017:1856
- https://access.redhat.com/errata/RHSA-2017:2392
- https://access.redhat.com/errata/RHSA-2017:2408
- https://bugzilla.redhat.com/show_bug.cgi?id=1313686
- https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html
- https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html
- https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html
- https://security.gentoo.org/glsa/201609-01
- http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0
- http://www.securityfocus.com/bid/86067
- http://www.ubuntu.com/usn/USN-2974-1
- https://access.redhat.com/errata/RHSA-2017:1856
- https://access.redhat.com/errata/RHSA-2017:2392
- https://access.redhat.com/errata/RHSA-2017:2408
- https://bugzilla.redhat.com/show_bug.cgi?id=1313686
- https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html
- https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01106.html
- https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01118.html
- https://security.gentoo.org/glsa/201609-01
Raw JSON (NVD)
Show
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