Research / Finding
BuildKit: ContainerID path escape F-BUILDKIT-001-001
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Root cause, affected code and disclosure timeline.
At a glance Conditions An attacker-controlled gateway frontend on a runc worker can use ContainerID paths to escape the executor root. What to do Upgrade affected BuildKit deployments to v0.28.1 or later; check that the worker actually runs the updated binary. 1seal reading guide, reviewed 2026-09-25 against the linked records. Not a new vendor assessment or a device rollout check.
Fix and severity by source Source assessments remain separate. Different CVSS versions are not a revision of one another. Code fixes, released versions and deployed updates are distinct evidence.
A ContainerID path escapes the runc executor root during a build: an identifier crosses a filesystem boundary.
Public snapshot: 26 Sep 2026. Status, releases and attribution belong to each source below; none is inferred from another record.
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Recorded evidence
8.4high
Malicious frontend can cause file escape outside of storage root
Fixed in: v0.28.1+
patched
details
Finding IDs F-BUILDKIT-001-001 CVE CVE-2026-33747 GHSA GHSA-4c29-8rgm-jvjj Status patched Fixed in v0.28.1+ CVSS vector CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVE registry state PUBLISHED CVE state checked 23 Sep 2026 Upstream title Malicious frontend can cause file escape outside of storage root Upstream publication 25 Mar 2026 Upstream updated 25 Mar 2026 Metadata fetched 23 Sep 2026 Upstream @1seal credit @1seal: reporter (accepted) F-BUILDKIT-001-001: File / path escapes. ContainerID traversal escapes the executor root. Reviewed 24 Sep 2026. Mechanism assessed by 1seal.
Mechanism source for F-BUILDKIT-001-001
Security area (1seal assessment): Authorization. ContainerID traversal escapes the executor root. Reviewed 24 Sep 2026.
8.4high
ContainerID path traversal in gateway frontend can escape runc executor root
Fixed in: v0.28.1+
Fix recorded not counted
details
Finding IDs F-BUILDKIT-001-001 CVE CVE-2026-33747 GHSA GHSA-4c29-8rgm-jvjj Status patched CWE CWE-22 Fixed in v0.28.1+ Disclosure date 25 Mar 2026 Recorded severity high CVSS vector CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H F-BUILDKIT-001-001: File / path escapes. ContainerID traversal escapes the executor root. Reviewed 24 Sep 2026. Mechanism assessed by 1seal.
Mechanism source for F-BUILDKIT-001-001
Security area (1seal assessment): Authorization. ContainerID traversal escapes the executor root. Reviewed 24 Sep 2026.
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How this page groups evidence This identifier groups recorded evidence; it is not an additional CVE, independent-vulnerability count or guarantee of vendor confirmation. Fixed code, released versions, attribution and independent discovery are distinct claims. Absent metadata means not recorded, not disproved. Counting rules .