CVE-2026-78205: Bentoml

Medium severity, CVSS 5.8. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Bentoml Bentoml: from 1.4.19, up to and including 1.4.39

Published 2026-08-24. Last modified 2026-09-24.