Vulnerability · Published Apr 6, 2026 · Assigned by GitHub_M
CVE-2026-35044BentoML has a Server-Side Template Injection via unsandboxed Jinja2 Environment in Dockerfile generation
High 8.8
In plain English
A high-severity security flaw in BentoML from bentoml. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
BentoML is a Python library for building online serving systems optimized for AI apps and model inference. Prior to 1.4.38, the Dockerfile generation function generate_containerfile() in src/bentoml/_internal/container/generate.py uses an unsandboxed jinja2.Environment with the jinja2.ext.do extension to render user-provided dockerfile_template files. When a victim imports a malicious bento archive and runs bentoml containerize, attacker-controlled Jinja2 template code executes arbitrary Python directly on the host machine, bypassing all container isolation. This vulnerability is fixed in 1.4.38.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | bentoml | 1.4.38 | GHSA-v959-cwq9-7hr6 |
| PyPI | bentoml | 1.4.38 | PYSEC-2026-159 |
Affected products (as reported)
Weakness: CWE-1336 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
- https://github.com/bentoml/BentoML/security/advisories/GHSA-v959-cwq9-7hr6 x_refsource_CONFIRM