CVE-2026-35044 (GCVE-0-2026-35044)

Vulnerability from cvelistv5 – Published: 2026-04-06 17:13 – Updated: 2026-04-06 18:49
VLAI
Title
BentoML has a Server-Side Template Injection via unsandboxed Jinja2 Environment in Dockerfile generation
Summary
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.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-06 18:49 UTC
CWE
  • CWE-1336 - Improper Neutralization of Special Elements Used in a Template Engine
Assigner
References
Impacted products
Vendor Product Version CPE status
bentoml BentoML Affected: < 1.4.38
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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