How severe is CVE-2021-3667?

CVE-2021-3667 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-2021-3667 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3667?

CVE-2021-3667 primarily affects Redhat Libvirt. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3667?

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

When was CVE-2021-3667 published?

CVE-2021-3667 was published on 2022-03-02 and last updated on 2026-06-17.

CVE-2021-3667

CVE-2021-3667 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: 3.5
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-667
Affected product: Redhat Libvirt
Published: 2022-03-02
Last modified: 2026-06-17

Description

An improper locking issue was found in the virStoragePoolLookupByTargetPath API of libvirt. It occurs in the storagePoolLookupByTargetPath function where a locked virStoragePoolObj object is not properly released on ACL permission failure. Clients connecting to the read-write socket with limited ACL permissions could use this flaw to acquire the lock and prevent other users from accessing storage pool/volume APIs, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.

Frequently asked questions

What is CVE-2021-3667?: An improper locking issue was found in the virStoragePoolLookupByTargetPath API of libvirt. It occurs in the storagePoolLookupByTargetPath function where a locked virStoragePoolObj object is not properly released on ACL permission failure. Clients connecting to the read-write socket with limited ACL permissions could use this flaw to acquire the lock and prevent other users from accessing storage pool/volume APIs, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.
How severe is CVE-2021-3667?: CVE-2021-3667 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-2021-3667 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3667?: CVE-2021-3667 primarily affects Redhat Libvirt. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3667?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3667 published?: CVE-2021-3667 was published on 2022-03-02 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:redhat:libvirt:*:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:advanced_virtualization:*:*:*
cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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