How severe is CVE-2021-4147?

CVE-2021-4147 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-4147 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4147?

CVE-2021-4147 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-2021-4147?

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

When was CVE-2021-4147 published?

CVE-2021-4147 was published on 2022-03-25 and last updated on 2026-06-17.

CVE-2021-4147

CVE-2021-4147 is a medium-severity vulnerability in Redhat Libvirt with a CVSS 3.x base score of 6.5. 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-667.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.9
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-667
Affected product: Redhat Libvirt
Published: 2022-03-25
Last modified: 2026-06-17

Description

A flaw was found in the libvirt libxl driver. A malicious guest could continuously reboot itself and cause libvirtd on the host to deadlock or crash, resulting in a denial of service condition.

Frequently asked questions

What is CVE-2021-4147?: A flaw was found in the libvirt libxl driver. A malicious guest could continuously reboot itself and cause libvirtd on the host to deadlock or crash, resulting in a denial of service condition.
How severe is CVE-2021-4147?: CVE-2021-4147 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-4147 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4147?: CVE-2021-4147 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-2021-4147?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4147 published?: CVE-2021-4147 was published on 2022-03-25 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:redhat:libvirt:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*

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