BuildKit vulnerable to malicious frontend causing file escape outside of storage root
Priority MEDIUM 43CWE-22Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 14 fixed, 16 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.
Summary
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, when using a custom BuildKit frontend, the frontend can craft an API message that causes files to be written outside of the BuildKit state directory for the execution context. The issue has been fixed in v0.28.1. The vulnerability requires using an untrusted BuildKit frontend set with `#syntax` or `--build-arg BUILDKIT_SYNTAX`. Using these options with a well-known frontend image like `docker/dockerfile` is not affected.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00507 43rd percentileScored 2026-11-07
Fix Partial buildkit (moby): 0.28.1github.com/moby/buildkit (Go): 0.28.1Red Hat: 15 advisoriesRed Hat: 14 fixed, 16 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| moby | buildkit | before 0.28.1 | 0.28.1 | Patch available | CNA |
| — | github.com/moby/buildkit (Go) | before 0.28.1 | 0.28.1 | Patch available | GHSA-4c29-8rgm-jvjj |
- buildkit Vendormoby Affected before 0.28.1 Fixed in 0.28.1 Patch available CNA
- github.com/moby/buildkit (Go) Vendor— Affected before 0.28.1 Fixed in 0.28.1 Patch available GHSA-4c29-8rgm-jvjj
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mobyproject:buildkit:*:*:*:*:*:*:*:* | before 0.28.1 | Vulnerable | Mobyproject |
- cpe:2.3:a:mobyproject:buildkit:*:*:*:*:*:*:*:* Versions before 0.28.1 Vulnerable ·Mobyproject
Remediation
- Fix · CNA buildkit (moby) Fixed in 0.28.1
- Fix · GHSA-4c29-8rgm-jvjj github.com/moby/buildkit (Go) Fixed in 0.28.1 Advisory →
Red Hat 15 advisories
- RHSA-2026:70267 Released 2026-09-22 · Red Hat rating ImportantRed Hat Quay 3.14.9
- Red Hat Quay 3.14 registry.redhat.io/quay/quay-rhel8
- RHSA-2026:57013 Released 2026-08-19 · Red Hat rating ImportantRed Hat OpenShift Data Foundation 4.20.17 security, enhancement & bug fix update
- Red Hat Openshift Data Foundation 4.20 registry.redhat.io/odf4/cephcsi-rhel9, registry.redhat.io/odf4/cephcsi-rhel9-operator, registry.redhat.io/odf4/mcg-core-rhel9 +19
- RHSA-2026:51033 Released 2026-08-06 · Red Hat rating ImportantRed Hat OpenShift API for Data Protection
- OpenShift API for Data Protection 1.3 registry.redhat.io/oadp/oadp-kubevirt-velero-plugin-rhel9, registry.redhat.io/oadp/oadp-mustgather-rhel9, registry.redhat.io/oadp/oadp-rhel9-operator +7
Show 12 more Red Hat advisories
- RHSA-2026:47388 Released 2026-07-28 · Red Hat rating Criticalmulticluster engine for Kubernetes v2.10.4 security update
- multicluster engine for Kubernetes 2.10 registry.redhat.io/multicluster-engine/cluster-image-set-controller-rhel9, registry.redhat.io/multicluster-engine/cluster-proxy-rhel9, registry.redhat.io/multicluster-engine/console-mce-rhel9 +4
- RHSA-2026:46885 Released 2026-07-27 · Red Hat rating Criticalmulticluster engine for Kubernetes v2.10.4 security update
- multicluster engine for Kubernetes 2.10 registry.redhat.io/multicluster-engine/cluster-image-set-controller-rhel9, registry.redhat.io/multicluster-engine/cluster-proxy-rhel9, registry.redhat.io/multicluster-engine/console-mce-rhel9 +4
- RHSA-2026:42644 Released 2026-07-21 · Red Hat rating ImportantRHOAI 2.25.9 - Red Hat OpenShift AI
- Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-feature-server-rhel9, registry.redhat.io/rhoai/odh-kserve-storage-initializer-rhel9 +36
- RHSA-2026:37387 Released 2026-07-09 · Red Hat rating ImportantRed Hat OpenShift Data Foundation 4.22.0 security, enhancement & bug fix update
- Red Hat Openshift Data Foundation 4.22 registry.redhat.io/odf4/cephcsi-rhel9, registry.redhat.io/odf4/cephcsi-rhel9-operator, registry.redhat.io/odf4/devicefinder-rhel9 +24
- RHSA-2026:30650 Released 2026-06-28 · Red Hat rating Importantmulticluster engine for Kubernetes v2.8.8 security update
- multicluster engine for Kubernetes 2.8 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/backplane-rhel9-operator, registry.redhat.io/multicluster-engine/console-mce-rhel9 +7
- RHSA-2026:29854 Released 2026-06-25 · Red Hat rating ImportantRed Hat OpenShift API for Data Protection
- OpenShift API for Data Protection 1.4 registry.redhat.io/oadp/oadp-kubevirt-velero-plugin-rhel9, registry.redhat.io/oadp/oadp-mustgather-rhel9, registry.redhat.io/oadp/oadp-rhel9-operator +7
- RHSA-2026:26568 Released 2026-06-17 · Red Hat rating ImportantRed Hat OpenShift API for Data Protection
- OpenShift API for Data Protection 1.5 registry.redhat.io/oadp/oadp-hypershift-velero-plugin-rhel9, registry.redhat.io/oadp/oadp-kubevirt-velero-plugin-rhel9, registry.redhat.io/oadp/oadp-mustgather-rhel9 +7
- RHSA-2026:22465 Released 2026-06-02 · Red Hat rating ImportantRed Hat Quay 3.17.2
- Red Hat Quay 3.17 registry.redhat.io/quay/quay-rhel9
- RHSA-2026:10125 Released 2026-04-23 · Red Hat rating ImportantRHTAS 1.3.4 - Red Hat Trusted Artifact Signer Release
- Red Hat Trusted Artifact Signer 1.3 registry.redhat.io/rhtas/client-server-rhel9
- RHSA-2026:9453 Released 2026-04-21 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.2.4
- Red Hat OpenShift Service Mesh 3.2 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
- RHSA-2026:9448 Released 2026-04-21 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.1.7
- Red Hat OpenShift Service Mesh 3.1 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
- RHSA-2026:9440 Released 2026-04-21 · Red Hat rating ImportantRed Hat OpenShift Service Mesh 3.0.10
- Red Hat OpenShift Service Mesh 3.0 registry.redhat.io/openshift-service-mesh/istio-cni-rhel9, registry.redhat.io/openshift-service-mesh/istio-pilot-rhel9, registry.redhat.io/openshift-service-mesh/istio-proxyv2-rhel9 +1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Assisted Installer for Red Hat OpenShift Container Platform 2 | Affected | No fix yet |
| Confidential Compute Attestation | Affected | No fix planned: Will not fix |
| Logging Subsystem for Red Hat OpenShift | Affected | No fix planned: Will not fix |
| Migration Toolkit for Containers | Affected | No fix yet |
| Migration Toolkit for Virtualization | Affected | No fix yet |
| Multicluster Engine for Kubernetes | Affected | No fix planned: Will not fix |
| OpenShift Developer Tools and Services | Affected | No fix yet |
| OpenShift Serverless | Affected | No fix planned: Will not fix |
| Pen Drive Powered by Red Hat Lightspeed | Affected | No fix planned: Will not fix |
| Red Hat Build of Podman Desktop | Affected | No fix planned: Will not fix |
| Red Hat Build of Podman Desktop - Tech Preview | Affected | No fix planned: Will not fix |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet |
| Red Hat OpenShift GitOps | Affected | No fix yet |
| Red Hat Quay 3 | Affected | No fix yet |
| Red Hat Trusted Artifact Signer | Affected | No fix yet |
| OpenShift API for Data Protection 1.3 | Fixed | RHSA-2026:51033 |
| OpenShift API for Data Protection 1.4 | Fixed | RHSA-2026:29854 |
| OpenShift API for Data Protection 1.5 | Fixed | RHSA-2026:26568 |
| Red Hat OpenShift AI 2.25 | Fixed | RHSA-2026:42644 |
| Red Hat OpenShift Service Mesh 3.0 | Fixed | RHSA-2026:9440 |
| Red Hat OpenShift Service Mesh 3.1 | Fixed | RHSA-2026:9448 |
| Red Hat OpenShift Service Mesh 3.2 | Fixed | RHSA-2026:9453 |
| Red Hat Openshift Data Foundation 4.20 | Fixed | RHSA-2026:57013 |
| Red Hat Openshift Data Foundation 4.22 | Fixed | RHSA-2026:37387 |
| Red Hat Quay 3.14 | Fixed | RHSA-2026:70267 |
| Red Hat Quay 3.17 | Fixed | RHSA-2026:22465 |
| Red Hat Trusted Artifact Signer 1.3 | Fixed | RHSA-2026:10125 |
| multicluster engine for Kubernetes 2.10 | Fixed | RHSA-2026:46885 |
| multicluster engine for Kubernetes 2.8 | Fixed | RHSA-2026:30650 |
Not affected: 30 products
- Kernel Module Management Operator for Red Hat Openshift
- Logical Volume Manager Storage
- Migration Toolkit for Applications 8
- Network Observability Operator
- Node HealthCheck Operator
- OpenShift API for Data Protection 1.3
- OpenShift API for Data Protection 1.4
- OpenShift API for Data Protection 1.5
- OpenShift Developer Tools and Services
- OpenShift Service Mesh 2
- OpenShift Service Mesh 3
- Power monitoring for Red Hat OpenShift
- Red Hat Advanced Cluster Management for Kubernetes 2
- Red Hat Ansible Automation Platform 2
- Red Hat Build of Kueue
- Red Hat Enterprise Linux 10
- Red Hat OpenShift AI (RHOAI)
- Red Hat OpenShift AI 2.25
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Dev Spaces
- Red Hat OpenShift Service Mesh 3.0
- Red Hat OpenShift Service Mesh 3.1
- Red Hat OpenShift Service Mesh 3.2
- Red Hat OpenStack Platform 18.0
- Red Hat Openshift Data Foundation 4.20
- Red Hat Openshift Data Foundation 4.22
- Red Hat Quay 3.14
- Red Hat Quay 3.17
- multicluster engine for Kubernetes 2.10
- multicluster engine for Kubernetes 2.8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-33747
- 2026-10-03 Alias added: GHSA-4c29-8rgm-jvjj
- 2026-10-09 Affected versions changed · Red Hat
- 2026-11-06 Fix available: RHSA-2026:42644 · Red Hat
References
More moby vulnerabilities
- TI-2026-14229 Tar extraction in moby/go-archive can write outside the destination directory via link following CVSS 4.0HIGH 7.1
- TI-2021-12512 Moby HyperKit uninitialized memory use in virtio-sock pci_vtsock_proc_tx CVSS 3.1HIGH 7.1
- TI-2024-27462 Moby authz zero length regression CVSS 3.1CRITICAL 10.0
- TI-2024-15672 BuildKit interactive containers API does not validate entitlements check CVSS 3.1CRITICAL 9.8
- TI-2024-15671 BuildKit possible host system access from mount stub cleaner CVSS 3.1CRITICAL 10.0
- TI-2026-26365 Moby: AuthZ plugin bypass with oversized request body CVSS 3.1HIGH 8.8
Sources
- CVE-2026-33747 · CVE Program
- CVE-2026-33747 · NVD
- FIRST EPSS
- GHSA-4c29-8rgm-jvjj · GitHub Advisory Database · CC BY 4.0
- CVE-2026-33747 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences