Vulnerability Description
BentoML's outbound connection safeguard (make_safe_connect in _internal/utils/uri.py) blocks private, loopback, and link-local IP addresses but fails to reject the RFC 6598 shared address space (100.64.0.0/10, CGNAT). In versions 1.4.19 through 1.4.39, an unauthenticated attacker can supply URLs pointing to that range via multipart file handling (MultipartSerde.ensure_file) or JSON request parsing (JSONSerde.parse_request), causing the server to make outbound requests to internal hosts on CGNAT networks (Server-Side Request Forgery). This is an incomplete fix for CVE-2025-54381.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/bentoml/BentoML
- https://github.com/bentoml/BentoML/blob/v1.4.39/src/bentoml/_internal/utils/uri.
- https://github.com/bentoml/BentoML/issues/5644
- https://www.vulncheck.com/advisories/bentoml-through-server-side-request-forgery
FAQ
What is CVE-2026-78205?
CVE-2026-78205 is a vulnerability with a CVSS score of 5.8 (MEDIUM). BentoML's outbound connection safeguard (make_safe_connect in _internal/utils/uri.py) blocks private, loopback, and link-local IP addresses but fails to reject the RFC 6598 shared address space (100.6...
How severe is CVE-2026-78205?
CVE-2026-78205 has been rated MEDIUM with a CVSS base score of 5.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-78205?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.