CVE-2019-20485: Input Validation

Published Dec 5, 2019
·
Updated

A flaw was found in the way Libvirtd daemon issued the 'suspend' command to a QEMU guest-agent running inside a guest. It holds a monitor job while issuing the 'suspend' command to a guest-agent. A malicious guest-agent may use this flaw to block the Libvirt daemon indefinitely resulting in a DoS scenario.

Upstream patch: --------------- -> https://libvirt.org/git/?p=libvirt.git;a=commitdiff;h=a663a860819287e041c3de672aad1d8543098ecc

Other sources

A flaw was found in the way the libvirtd daemon issued the 'suspend' command to a QEMU guest-agent running inside a guest, where it holds a monitor job while issuing the 'suspend' command to a guest-agent. A malicious guest-agent may use this flaw to block the libvirt daemon indefinitely, resulting in a denial of service.

qemu/qemudriver.c in libvirt before 6.0.0 mishandles the holding of a monitor job during a query to a guest agent, which allows attackers to cause a denial of service (API blockage).

Affected Software

9 affected componentsFixes available
redhat/libvirt<0:4.5.0-36.el7
0:4.5.0-36.el7
redhat/libvirt<6.0.0
6.0.0
debian/libvirt<=5.6.0-2, <=5.6.0-3
redhat libvirt<6.0.0
Debian Debian Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Fedoraproject Fedora=31
debian/libvirt
7.0.0-3+deb11u39.0.0-4+deb12u211.3.0-3+deb13u212.0.0-1

Event History

Dec 5, 2019
CVE Published
12:00 AM
Mar 19, 2020
CVE Published
via MITRE·01:29 AM
Data Sourced
via MITRE·01:29 AM
Description
Feb 23, 2026
Data Sourced
via Debian·03:18 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2019-20485?

CVE-2019-20485 is a vulnerability found in libvirt where the libvirtd daemon can be blocked indefinitely by a malicious guest-agent.

2

How does CVE-2019-20485 affect libvirt?

CVE-2019-20485 affects libvirt by allowing a malicious guest-agent to block the libvirtd daemon indefinitely.

3

What is the severity rating of CVE-2019-20485?

CVE-2019-20485 has a severity rating of 5.8 (High).

4

How can I fix CVE-2019-20485?

To fix CVE-2019-20485, update libvirt to version 6.0.0 or higher.

5

Where can I find more information about CVE-2019-20485?

You can find more information about CVE-2019-20485 at the following references: [link1], [link2], [link3].

Contact

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