Security readout for executives and security teams
Plain-English summary
This Kubernetes CSI issue could let a highly privileged user access or alter PersistentVolume data through snapshot, restore, clone, or resize operations. The score is medium because exploitation requires high privileges, user interaction, and high complexity, but the business impact can be serious where storage contains sensitive tenant or application data.
Executive priority
Prioritize this for Kubernetes environments with sensitive data in PersistentVolumes or multi-team cluster tenancy. It is not marked as actively exploited in the provided sources, but unauthorized storage access can create material data exposure if vulnerable CSI sidecars remain deployed.
Technical view
CVE-2019-11255 is improper input validation in Kubernetes CSI external-provisioner, external-snapshotter, and external-resizer sidecars. Vulnerable versions can mishandle snapshot, cloning, restore-from-snapshot, and resize workflows, enabling unauthorized PersistentVolume data access or mutation. The CVSS 3.1 score is 4.8 with high confidentiality impact and low integrity impact.
Likely exposure
Exposure is most likely in Kubernetes environments using CSI sidecars for volume snapshotting, cloning, or resizing, especially older clusters or vendor distributions retaining affected sidecar versions. Clusters not using these CSI features or not running the affected sidecars are less likely exposed.
Exploitation context
The bundle does not show CISA KEV listing or active exploitation. The CVSS vector indicates network reachability but high attack complexity, high privileges, and required user interaction. Treat exploitation as plausible only in environments where an attacker already has meaningful Kubernetes permissions around storage workflows.
Researcher notes
Evidence is limited to public CVE, Kubernetes, mailing-list, Red Hat, and NetApp references. The bundle identifies affected sidecar components and version ranges but does not provide exploit details. Avoid assuming exposure from Kubernetes version alone; validate deployed CSI sidecar images and enabled storage workflows.
Mitigation direction
- Inventory CSI external-provisioner, external-snapshotter, and external-resizer sidecar versions across clusters.
- Upgrade affected CSI sidecars to vendor-supported fixed versions named in Kubernetes or distribution advisories.
- Replace external-resizer v0.1 or v0.2 following Kubernetes CSI security release guidance.
- Review Red Hat, NetApp, and Kubernetes advisories for distribution-specific fixed packages.
- Restrict snapshot, clone, restore, and resize permissions to trusted Kubernetes roles only.
Validation and detection
- Check running CSI sidecar image tags against the affected version ranges in the CVE record.
- Confirm whether snapshot, clone, restore-from-snapshot, or resize features are enabled.
- Review Kubernetes RBAC granting storage snapshot, PersistentVolumeClaim, and resize capabilities.
- Check vendor advisory applicability for managed platforms, OpenShift, or NetApp-integrated deployments.
- Look for unexpected PersistentVolume snapshot, restore, clone, or resize activity in audit logs.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-20: Exact CWE lookup
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Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2019-11255 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:N0.54.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.8MediumVector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/kubernetes/kubernetes/issues/85233CVE reference · x_refsource_CONFIRM
- Security release of kubernetes-csi sidecars - CVE-2019-11255CVE reference · mailing-list, x_refsource_MLIST
- RHSA-2019:4099CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2019:4096CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2019:4054CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2019:4225CVE reference · vendor-advisory, x_refsource_REDHAT
- https://security.netapp.com/advisory/ntap-20200810-0003/CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.