CVE-2016-4020

Publication date 14 April 2016

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

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).

Status

Package Ubuntu Release Status
qemu 16.04 LTS xenial
Fixed 1:2.5+dfsg-5ubuntu10.1
15.10 wily
Fixed 1:2.3+dfsg-5ubuntu9.4
14.04 LTS trusty
Fixed 2.0.0+dfsg-2ubuntu1.24
12.04 LTS precise Not in release
qemu-kvm 16.04 LTS xenial Not in release
15.10 wily Not in release
14.04 LTS trusty Not in release
12.04 LTS precise
Not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
qemu

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.5 · Medium

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

References

Related Ubuntu Security Notices (USN)

Other references

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