{"id":"CVE-2026-55245","state":"PUBLISHED","title":"Bifrost: SSRF deny-list incomplete: isPublicIP permits CGNAT, IPv6 6to4/NAT64, and site-local in FetchAndEncodeURL","description":"Bifrost is an enterprise AI gateway for routing requests to model providers. Prior to 1.5.17, the isPublicIP function in core/providers/utils/fetch.go, reached through FetchAndEncodeURL for Bedrock and Vertex image or document URLs, classifies Carrier-Grade NAT 100.64.0.0/10, IPv6 6to4 2002::/16, NAT64 64:ff9b::/96 and 64:ff9b:1::/48, and deprecated IPv6 site-local fec0::/10 addresses as public. A remote attacker who controls a multimodal request URL can make the gateway fetch internal services, including a cloud instance metadata endpoint encoded through 6to4 or NAT64. This issue is fixed in version 1.5.17.","publishedAt":"2026-08-28T18:24:16.723Z","updatedAt":"2026-08-28T19:54:10.966Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["maximhq bifrost"],"affected":[{"vendor":"maximhq","product":"bifrost","versions":[{"version":"< 1.5.17","status":"affected"}]}],"references":["https://github.com/maximhq/bifrost/security/advisories/GHSA-w98g-5w9p-p3rc","https://github.com/maximhq/bifrost/pull/4092","https://github.com/maximhq/bifrost/commit/54ec431fc5255ff42c36420d88549477e0b33d89","https://github.com/maximhq/bifrost/releases/tag/core/v1.5.17"],"weaknesses":["CWE-918"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55245.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55245","state":"PUBLISHED","datePublished":"2026-08-28T18:24:16.723Z","dateUpdated":"2026-08-28T19:54:10.966Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-16T16:44:00.624Z"},"containers":{"cna":{"title":"Bifrost: SSRF deny-list incomplete: isPublicIP permits CGNAT, IPv6 6to4/NAT64, and site-local in FetchAndEncodeURL","descriptions":[{"lang":"en","value":"Bifrost is an enterprise AI gateway for routing requests to model providers. Prior to 1.5.17, the isPublicIP function in core/providers/utils/fetch.go, reached through FetchAndEncodeURL for Bedrock and Vertex image or document URLs, classifies Carrier-Grade NAT 100.64.0.0/10, IPv6 6to4 2002::/16, NAT64 64:ff9b::/96 and 64:ff9b:1::/48, and deprecated IPv6 site-local fec0::/10 addresses as public. A remote attacker who controls a multimodal request URL can make the gateway fetch internal services, including a cloud instance metadata endpoint encoded through 6to4 or NAT64. This issue is fixed in version 1.5.17."}],"affected":[{"vendor":"maximhq","product":"bifrost","versions":[{"version":"< 1.5.17","status":"affected"}]}],"references":[{"url":"https://github.com/maximhq/bifrost/security/advisories/GHSA-w98g-5w9p-p3rc","name":"https://github.com/maximhq/bifrost/security/advisories/GHSA-w98g-5w9p-p3rc","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/maximhq/bifrost/pull/4092","name":"https://github.com/maximhq/bifrost/pull/4092","tags":["x_refsource_MISC"]},{"url":"https://github.com/maximhq/bifrost/commit/54ec431fc5255ff42c36420d88549477e0b33d89","name":"https://github.com/maximhq/bifrost/commit/54ec431fc5255ff42c36420d88549477e0b33d89","tags":["x_refsource_MISC"]},{"url":"https://github.com/maximhq/bifrost/releases/tag/core/v1.5.17","name":"https://github.com/maximhq/bifrost/releases/tag/core/v1.5.17","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-28T18:24:16.723Z"},"source":{"advisory":"GHSA-w98g-5w9p-p3rc","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/maximhq/bifrost/security/advisories/GHSA-w98g-5w9p-p3rc","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-28T19:54:05.268770Z","id":"CVE-2026-55245","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-28T19:54:10.966Z"}}]}}}