CVE-2026-78205

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 v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/bentoml/BentoML
https://github.com/bentoml/BentoML/blob/v1.4.39/src/bentoml/_internal/utils/uri.py#L89-L96
https://github.com/bentoml/BentoML/issues/5644
https://www.vulncheck.com/advisories/bentoml-through-server-side-request-forgery-via-unfiltered-rfc-6598-shared-address-space

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-24 01:16

Updated : 2026-08-24 19:17

NVD link : CVE-2026-78205

Mitre link : CVE-2026-78205

CVE.ORG link : CVE-2026-78205

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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