BentoML is a Python library used for building online serving systems optimized for AI applications and model inference. The issue occurs because the template `src/bentoml/ internal/container/frontend/dockerfile/templates/base v2.j2` interpolates the `docker.base image` variable without escaping, newline filtering, or validation. A malicious `bento.yaml` file containing a multi-line value for `docker.base image` can smuggle arbitrary Dockerfile directives into the generated Dockerfile. When the `bentoml containerize` command is executed, it triggers a docker build that runs the injected `RUN` directives on the host system.