How severe is CVE-2019-3840?

CVE-2019-3840 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-3840 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-3840?

CVE-2019-3840 primarily affects Redhat Libvirt. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-3840?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-3840 published?

CVE-2019-3840 was published on 2019-03-27 and last updated on 2026-06-17.

CVE-2019-3840

CVE-2019-3840 is a medium-severity vulnerability in Redhat Libvirt with a CVSS 3.x base score of 5.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v2: 3.5
EPSS exploit prediction: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Redhat Libvirt
Published: 2019-03-27
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2019-3840?: 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 severe is CVE-2019-3840?: CVE-2019-3840 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-3840 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-3840?: CVE-2019-3840 primarily affects Redhat Libvirt. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-3840?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-3840 published?: CVE-2019-3840 was published on 2019-03-27 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:redhat:libvirt:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.0:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:42.3:*:*:*:*:*:*:*

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