build(deps): bump github.com/moby/buildkit from 0.24.0 to 0.28.1 in /tools/get-deps

[dependabot]

Bumps github.com/moby/buildkit from 0.24.0 to 0.28.1.

Release notes

Sourced from github.com/moby/buildkit's releases.

v0.28.1

Welcome to the v0.28.1 release of buildkit!

Please try out the release binaries and report any issues at https://github.com/moby/buildkit/issues.

Contributors

• Tõnis Tiigi
• CrazyMax
• Sebastiaan van Stijn

Notable Changes

• Fix insufficient validation of Git URL #ref:subdir fragments that could allow access to restricted files outside the checked-out repository root. GHSA-4vrq-3vrq-g6gg
• Fix a vulnerability where an untrusted custom frontend could cause files to be written outside the BuildKit state directory. GHSA-4c29-8rgm-jvjj
• Fix a panic when processing invalid .dockerignore patterns during COPY. #6610 moby/patternmatcher#9

Dependency Changes

• github.com/moby/patternmatcher v0.6.0 -> v0.6.1

Previous release can be found at v0.28.0

v0.28.0

buildkit 0.28.0

Welcome to the v0.28.0 release of buildkit!

Please try out the release binaries and report any issues at https://github.com/moby/buildkit/issues.

Contributors

• Tõnis Tiigi
• CrazyMax
• Sebastiaan van Stijn
• Jonathan A. Sternberg
• Akihiro Suda
• Amr Mahdi
• Dan Duvall
• David Karlsson
• Jonas Geiler
• Kevin L.
• rsteube

... (truncated)

Commits

• 45b038c git: normalize and validate subdir paths
• f5462c2 git: harden ref arg handling
• 71577a5 source: extract SafeFileName into shared pathutil package
• df43783 source/http: use os.Root for saved file operations
• 9ce6f62 source/http: sanitize downloaded filenames
• 099cf80 executor: validate container IDs centrally
• 2642113 Merge pull request #6610 from thaJeztah/0.28_backport_bump_patternmatcher
• 802da78 vendor: github.com/moby/patternmatcher v0.6.1
• 5245d86 Merge pull request #6551 from tonistiigi/v0.28-cherry-picks
• 90ee5de vendor: update x/net to v0.51.0
• Additional commits viewable in compare view

Note
Automatic rebases have been disabled on this pull request as it has been open for over 30 days.

[eriknordmark]

@dependabot rebase

[eriknordmark]

Current investigation for the buildkit/linuxkit compatibility build failure is:
Conclusion

There is no version of linuxkit — tagged or untagged, including master HEAD —
that is compatible with buildkit v0.28.1. Linuxkit's latest buildkit
dependency is v0.26.3, and the ConfigFile removal happened in v0.28.x.
Linuxkit simply hasn't adopted the new API yet.

The only viable path (without modifying vendor code) would be to revert the
buildkit dependency to v0.27.x or earlier until linuxkit catches up. Would you
like to explore pinning buildkit to an older version that still has the
ConfigFile field?

[eriknordmark]

Some more analysis by claude:
● Analysis: CVE-2026-33747 and CVE-2026-33748 in EVE

Bottom line: Neither CVE is reachable in EVE's usage of buildkit.

CVE Details

CVE-2026-33747 (CVSS 8.4–9.8 HIGH/CRITICAL) — Malicious custom BuildKit
frontend can write files outside the BuildKit state directory (path traversal
on writes). Requires an untrusted custom frontend (via #syntax=... or
--build-arg BUILDKIT_SYNTAX=...).

CVE-2026-33748 (CVSS 7.5–8.2 HIGH) — Insufficient validation of Git URL subdir
fragments (#:) can allow reading files outside the
checked-out repo root. Requires a buildkit build invoked with a Git URL
containing a subdir component.

Both vulnerabilities live in the buildkit daemon code paths (solver, source,
cache subsystems) — not in the parser/client library.

EVE's Buildkit Usage

Buildkit appears in three build-time tools only — zero usage in any on-device
runtime component (pkg/pillar, etc.):

┌────────────────────────┬─────────┬─────────┬────────────┬────────────┐
│ │ │ Vulnera │ CVE-2026-3 │ CVE-2026-3 │
│ Module │ Version │ ble ver │ 3747 │ 3748 │
│ │ │ sion? │ reachable │ reachable │
├────────────────────────┼─────────┼─────────┼────────────┼────────────┤
│ tools/dockerfile-from- │ 0.28.1 │ │ │ │
│ checker │ (patche │ No │ No │ No │
│ │ d) │ │ │ │
├────────────────────────┼─────────┼─────────┼────────────┼────────────┤
│ tools/get-deps │ 0.24.0 │ Yes │ No │ No │
├────────────────────────┼─────────┼─────────┼────────────┼────────────┤
│ eve-tools/bpftrace-com │ 0.23.2 │ │ │ │
│ piler │ (indire │ Yes │ No │ No │
│ │ ct) │ │ │ │
└────────────────────────┴─────────┴─────────┴────────────┴────────────┘

Why not reachable in tools/get-deps and bpftrace-compiler: Both tools only use
buildkit as a static Dockerfile parser (frontend/dockerfile/parser,
frontend/dockerfile/instructions, frontend/dockerfile/shell). The
buildkitClient.Client type imported in get-deps is only used as the return
type of a dry-run stub that unconditionally returns nil, nil — no daemon is
ever started, no build is executed, no Git URL or custom frontend is
processed. The vulnerable daemon-side code paths are simply never called.

Recommendation

The vulnerabilities are not exploitable in EVE's current build tooling.
However, tools/get-deps (v0.24.0) and eve-tools/bpftrace-compiler (v0.23.2
indirect) carry vulnerable versions, which will continue to generate scanner
findings. Bumping both to v0.28.1 would resolve the findings and is good
hygiene, even though there is no practical exploitability today.