CVE-2019-3840: A NULL pointer dereference flaw was discovered in libvirt before version 5.0.0 in the way it gets interface in

Q: How do I fix CVE-2019-3840?

libvirt: upgrade to 5.0.0; leap: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2019-3840 being exploited?

CVE-2019-3840 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2019-3840 affect?

CVE-2019-3840 affects libvirt, leap. Severity is medium (CVSS 5.8). A NULL pointer dereference flaw was discovered in libvirt before version 5.0.0 in the way it gets interface information through the QEMU agent. An attacker in a guest VM can use this flaw to crash libvirtd and cause a denial of service.

Q: How urgent is CVE-2019-3840?

Priority 49/100. Public exploit reference; On your watchlist

This month

MEDIUM 5.8WATCHLISTUPGRADEMITIGATE

CVE-2019-3840 is a medium-severity flaw (CVSS 5.8) affecting libvirt, leap. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A NULL pointer dereference flaw was discovered in libvirt before version 5.0.0 in the way it gets interface information through the QEMU agent. An attacker in a guest VM can use this flaw to crash libvirtd and cause a denial of service.

Why this priority

Public exploit reference
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	5.8 (Medium)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	Low
User interaction	Required
EPSS exploit chance	1.5% (top 26%)
CISA exploited list	No
Weakness	CWE-476
Published	2019-03-27
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: opensuse · redhat

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-03-27 13:29 UTCPublished CVE record published
2026-06-17 02:35 UTCUpdated Record last modified

redhat libvirt UPGRADE

Affected: < 5.0.0

Fixed in: 5.0.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy libvirt || rpm -q libvirt || libvirt --version

2. UPGRADE to 5.0.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade libvirt

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade libvirt

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

opensuse leap MITIGATE

Affected: 15.0 · 42.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 15.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2019-3840?

libvirt: upgrade to 5.0.0; leap: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2019-3840 being exploited?

CVE-2019-3840 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2019-3840 affect?

CVE-2019-3840 affects libvirt, leap. Severity is medium (CVSS 5.8). A NULL pointer dereference flaw was discovered in libvirt before version 5.0.0 in the way it gets interface information through the QEMU agent. An attacker in a guest VM can use this flaw to crash libvirtd and cause a denial of service.

How urgent is CVE-2019-3840?

Priority 49/100. Public exploit reference; On your watchlist

Software pages

QEMU vulnerabilities

Related CVEs

CVE-2024-8235 MEDIUM 6.2 UPGRADE A flaw was found in libvirt
CVE-2024-2496 MEDIUM 5.0 UPGRADE MITIGATE A NULL pointer dereference flaw was found in the udevConnectListAllInterfaces() function in libvirt
CVE-2023-3750 MEDIUM 6.5 MITIGATE MITIGATE A flaw was found in libvirt
CVE-2023-2700 MEDIUM 5.5 DOWNGRADE MITIGATE A vulnerability was found in libvirt
CVE-2022-0897 MEDIUM 4.3 UPGRADE MITIGATE A flaw was found in the libvirt nwfilter driver

References

← Back to latest CVEs