fix(dockerfile): disable followlinks in Jinja2 FileSystemLoader#5612
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ibondarenko1 wants to merge 1 commit into
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fix(dockerfile): disable followlinks in Jinja2 FileSystemLoader#5612ibondarenko1 wants to merge 1 commit into
ibondarenko1 wants to merge 1 commit into
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FileSystemLoader(templates_path, followlinks=True) resolves through
symlinks when an {% include %} or {% extends %} references a relative
path. The built-in templates path is package-internal and does not
need symlink resolution. The user-template overlay path is
build-context controlled; following symlinks there is the same class
of issue CVE-2026-40610 mitigated for the outer build context.
Defense-in-depth on CVE-2026-40610.
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Why
generate.pyconfiguresFileSystemLoader(templates_path, followlinks=True)in two places (built-in templates loader and user-template overlay loader). Jinja2 default isfollowlinks=False; BentoML explicitly opts in.The built-in templates path is package-internal and does not need symlink resolution. The user-template overlay path is build-context controlled. If the build context contains symlinks, Jinja2 resolves through them when an
{% include %}or{% extends %}uses a relative path. CVE-2026-40610 fixed the outer build-context symlink traversal but did not address the per-template Jinja2 resolver.What
Flip both occurrences to
followlinks=False. Two-line change. Defense-in-depth on CVE-2026-40610.Impact
Any user who currently uses symlinks inside their Dockerfile-template directory would see a
TemplateNotFounderror and need to copy the file directly instead. Search ofgh issues/PRsshows no reports of this pattern in use; ship with a release-notes line.Testing
pytest tests/unit/_internal/container/test_generate.py(existing).dockerfile_templatefield, verify it still renders.