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.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.4%top 65.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

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

EcosystemPackageFixed inAdvisory
PyPIbentoml1.4.38GHSA-v959-cwq9-7hr6
PyPIbentoml1.4.38PYSEC-2026-159

Affected products (as reported)

VendorProductVersions
bentoml BentoML < 1.4.38

Weakness: CWE-1336 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References