Description
BuildKit's cache mount source= selector on Windows Container on Windows (WCOW) workers does not detect NTFS directory junctions placed inside the cache root. A build authored by an untrusted user on a WCOW-configured BuildKit daemon can read arbitrary host files reachable to the BuildKit daemon process.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| moby | BuildKit | < 0.31.2 | 0.31.2 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | buildah +1 | 2:1.44.0-3.2.hum1 | RHSA-2026:51065, RHSA-2026:43122 |
| Red Hat Hardened Images 1 | podman +5 | 5:6.0.2-2.1.hum1 | RHSA-2026:44152 |
| Red Hat Hardened Images 1 | trivy | 0.72.0-0.1.2.hum1 | RHSA-2026:46988 |
Advisories 4
- RHSA-2026:44152 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:51065 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:43122 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:46988 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Oct 20, 2026