moby/buildkit · Security
BuildKit Git URL subdir component can cause access to restricted files
- GHSA ID
- GHSA-4vrq-3vrq-g6gg
- CVE ID
- CVE-2026-33748
- Severity
- high
- Published
- Updated
- CVSS
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CVSS v3
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CVSS v4
- 8.2 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Description
Impact
Insufficient validation of Git URL fragment subdir components (<url>#<ref>:<subdir>, docs) may allow access to files outside the checked-out Git repository root. Possible access is limited to files on the same mounted filesystem.
Patches
The issue has been fixed in version v0.28.1
Workarounds
The issue affects only builds that use Git URLs with a subpath component. 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.
CWEs
- CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
- CWE-59 · Improper Link Resolution Before File Access ('Link Following')