{"id":"CVE-2026-78205","summary":"BentoML 1.4.19 through 1.4.39 Server-Side Request Forgery via Unfiltered RFC 6598 Shared Address Space","details":"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.","modified":"2026-08-27T11:31:10.823685320Z","published":"2026-08-24T00:30:45.786Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/78xxx/CVE-2026-78205.json","cna_assigner":"VulnCheck","cwe_ids":["CWE-918"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/78xxx/CVE-2026-78205.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-78205"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/bentoml-through-server-side-request-forgery-via-unfiltered-rfc-6598-shared-address-space"},{"type":"REPORT","url":"https://github.com/bentoml/BentoML/issues/5644"},{"type":"PACKAGE","url":"https://github.com/bentoml/BentoML"},{"type":"ARTICLE","url":"https://github.com/bentoml/BentoML/blob/v1.4.39/src/bentoml/_internal/utils/uri.py#L89-L96"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/bentoml/bentoml","events":[{"introduced":"a51b1a13a52a5f5abd9795c2d6d17fe4150dd9e4"},{"fixed":"e570eb2b1dd5ea49c09c261232a6b131a023d1b2"}],"database_specific":{"source":["AFFECTED_FIELD","DESCRIPTION"],"extracted_events":[{"introduced":"1.4.19"},{"last_affected":"1.4.39"},{"fixed":"1.4.39"}]}}],"versions":["v1.4.38","v1.4.36","v1.4.35","v1.4.34","v1.4.33","v1.4.32","v1.4.31","v1.4.30","v1.4.29","v1.4.28","v1.4.27","v1.4.26","v1.4.25","v1.4.24","v1.4.23","v1.4.22","v1.4.21","v1.4.20","v1.4.19"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-78205.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N"}]}