CVE-2026-78205

Name of the Vulnerable Software and Affected Versions BentoML versions 1.4.19 through 1.4.39

Description The outbound connection safeguard make safe connect() in internal/utils/uri.py fails to reject the RFC 6598 shared address space (100.64.0.0/10), which is used for Carrier-Grade NAT (CGNAT). An unauthenticated attacker can exploit this by providing URLs pointing to this range through the MultipartSerde.ensure file() function during multipart file handling or the JSONSerde.parse request() function during JSON request parsing. This leads to Server-Side Request Forgery (SSRF), where the server is forced to make outbound requests to internal hosts on CGNAT networks.

Recommendations Update BentoML to a version later than 1.4.39. As a temporary mitigation, restrict the use of MultipartSerde.ensure file() and JSONSerde.parse request() when handling untrusted user input.