Path Traversal in Moby Buildkit
CVE-2026-33748
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner. Prior to version 0.28.1, insufficient validation of Git URL fragment subdir components may allow access to files outside the checked-out Git repository root. Possible access is limited to files on the same mounted filesystem. The issue has been fixed in version v0.28.1 The issue affects only builds that use Git URLs with a subpath component. As a workaround, avoid building Dockerfiles from untrusted sources or using the subdir component from an untrusted Git repository where the subdir component could point to a symlink.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: -0.000
Affected products
- Moby Buildkit — versions < 0.28.1
- Mobyproject Buildkit
Weakness classification (CWE)
References
- github.com/moby/buildkit/security/advisories/GHSA-4vrq-3vrq-g6gg (Mitigation, Vendor Advisory)
- docs.docker.com/build/concepts/context/ (Product)
- github.com/moby/buildkit/releases/tag/v0.28.1 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-33748?
- CVE-2026-33748 is a high-severity vulnerability in Moby Buildkit, classified under Path Traversal. CVSS score: 7.5/10. Published 2026-03-27.
- How severe is CVE-2026-33748?
- High severity. CVSS v3 base score is 7.5 out of 10.