{"cve":"CVE-2016-4020","nvd":{"published":"2016-05-25T15:59:04.927","modified":"2026-06-17T00:46:44.877","status":"Modified","description":"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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N","score":6.5},"cwes":[],"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"],"products":["canonical:ubuntu_linux","debian:debian_linux","qemu:qemu","redhat:enterprise_linux_desktop","redhat:enterprise_linux_eus","redhat:enterprise_linux_server","redhat:enterprise_linux_server_aus","redhat:enterprise_linux_server_tus","redhat:enterprise_linux_workstation","redhat:openstack","redhat:virtualization"],"source":"nvd","synced_at":"2026-10-19T20:38:51.654415212+00:00"},"epss":{"cve":"CVE-2016-4020","score":0.00372,"percentile":0.31193,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}