CVE-2016-4020 Information disclosure in n/a

What is CVE-2016-4020?

CVE-2016-4020 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 25 May 2016. It can only be exploited from the same machine or local network, with no action from the victim.

Official 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).

Which versions are affected by CVE-2016-4020?

It affects 11 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Qemu Qemu, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Eus, Redhat Enterprise Linux Server and 5 more.

How do I fix CVE-2016-4020?

Apply the vendor's patch.

Is CVE-2016-4020 being exploited?

There is no known exploitation of CVE-2016-4020 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2016-4020, GHSA-vcqr-cc8h-57gj, UBUNTU-CVE-2016-4020.