How severe is CVE-2021-3559?

CVE-2021-3559 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3559 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3559?

CVE-2021-3559 primarily affects Redhat Libvirt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3559?

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

When was CVE-2021-3559 published?

CVE-2021-3559 was published on 2021-05-24 and last updated on 2026-06-17.

CVE-2021-3559

CVE-2021-3559 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-119.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-119
Affected product: Redhat Libvirt
Published: 2021-05-24
Last modified: 2026-06-17

Description

A flaw was found in libvirt in the virConnectListAllNodeDevices API in versions before 7.0.0. It only affects hosts with a PCI device and driver that supports mediated devices (e.g., GRID driver). This flaw could be used by an unprivileged client with a read-only connection to crash the libvirt daemon by executing the 'nodedev-list' virsh command. The highest threat from this vulnerability is to system availability.

Frequently asked questions

What is CVE-2021-3559?: A flaw was found in libvirt in the virConnectListAllNodeDevices API in versions before 7.0.0. It only affects hosts with a PCI device and driver that supports mediated devices (e.g., GRID driver). This flaw could be used by an unprivileged client with a read-only connection to crash the libvirt daemon by executing the 'nodedev-list' virsh command. The highest threat from this vulnerability is to system availability.
How severe is CVE-2021-3559?: CVE-2021-3559 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3559 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3559?: CVE-2021-3559 primarily affects Redhat Libvirt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3559?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3559 published?: CVE-2021-3559 was published on 2021-05-24 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:redhat:libvirt:*:*:*:*:*:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*

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