CVE-2026-3864

CVE-2026-3864 is a medium-severity vulnerability 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-22.

Key facts

Description

A vulnerability was discovered in the Kubernetes CSI Driver for NFS where the subDir parameter in volume identifiers was insufficiently validated. Attackers with the ability to create PersistentVolumes referencing the NFS CSI driver could craft volume identifiers containing path traversal sequences (../). During volume deletion or cleanup operations, the driver could operate on unintended directories outside the intended managed path within the NFS export. This may lead to deletion or modification of directories on the NFS server.

Frequently asked questions

What is CVE-2026-3864?
A vulnerability was discovered in the Kubernetes CSI Driver for NFS where the subDir parameter in volume identifiers was insufficiently validated. Attackers with the ability to create PersistentVolumes referencing the NFS CSI driver could craft volume identifiers containing path traversal sequences (../). During volume deletion or cleanup operations, the driver could operate on unintended directories outside the intended managed path within the NFS export. This may lead to deletion or modification of directories on the NFS server.
How severe is CVE-2026-3864?
CVE-2026-3864 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2026-3864 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-3864?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3864 have an EU (EUVD) identifier?
Yes. CVE-2026-3864 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-13831.
When was CVE-2026-3864 published?
CVE-2026-3864 was published on 2026-03-20 and last updated on 2026-06-17.

References

Other CWE-22 (Path Traversal) vulnerabilities

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