{"id":"CVE-2026-46678","published":"2026-07-29T20:16:45Z","modified":"2026-07-30T14:37:27Z","title":"Pydantic AI: SSRF cloud-metadata blocklist bypass via IPv4-mapped IPv6 (Incomplete fix of CVE-2026-25580)","vendor":"pydantic","product":"pydantic-ai","tier":"tail","description":{"text":"Pydantic AI is a Python agent framework for building Generative AI applications. In versions 1.56.0 through 1.98.0, when an application opts a URL into force_download='allow-local' (disabling the default block on private/internal IPs), the cloud-metadata blocklist could be bypassed by encoding the metadata IP in an IPv6 transition form (IPv4-mapped IPv6, 6to4, or NAT64), exposing cloud IAM short-term credentials on dual-stack or translated networks. This is an incomplete fix of GHSA-2jrp-274c-jhv3 / CVE-2026-25580, whose remediation did not hold for IPv6-encoded forms of the metadata IPs. An application is affected only if it explicitly opts a FileUrl (ImageUrl, AudioUrl, VideoUrl, DocumentUrl) into force_download='allow-local' on a URL influenced by untrusted input; it is not affected when using bundled integrations to ingest user input (Agent.to_web / clai web, VercelAIAdapter, AGUIAdapter / Agent.to_ag_ui), since they do not propagate force_download from external data, nor when downloading only from developer-controlled URLs. This issue has been fixed in version 1.99.0.","provenance":"source","from":"CVE.org"},"cvss":{"score":6.8,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N","provenance":"source","from":"CVE.org CNA"},"epss":{"score":0.0038,"percentile":0.31921,"provenance":"source"},"cwes":[{"id":"CWE-918","name":"Server-Side Request Forgery"}],"references":[{"url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-cqp8-fcvh-x7r3","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/pydantic/pydantic-ai/releases/tag/v1.99.0","tags":["x_refsource_MISC"]}],"priority":{"score":11.1,"factors":[{"name":"EPSS percentile","points":6.38},{"name":"CVSS severity","points":4.76}]},"vendorSlug":"pydantic","affectedVersions":[{"vendor":"pydantic","product":"pydantic-ai","versions":[">= 1.56.0, < 1.99.0"]},{"vendor":"pydantic","product":"pydantic-ai-slim","versions":[">= 1.56.0, < 1.99.0"]}],"affected":[{"ecosystem":"PyPI","package":"pydantic-ai","vulnerableRanges":[">=1.56.0, <1.99.0"],"patched":["1.99.0"],"from":["GHSA-cqp8-fcvh-x7r3","PYSEC-2026-2978"],"provenance":"source"},{"ecosystem":"PyPI","package":"pydantic-ai-slim","vulnerableRanges":[">=1.56.0, <1.99.0"],"patched":["1.99.0"],"from":["GHSA-cqp8-fcvh-x7r3","PYSEC-2026-2982"],"provenance":"source"}],"euvd":{"id":"EUVD-2026-50561","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-pydantic-ai-cve-2026-25580","parents":[{"from":"CVE-2026-25580","to":"CVE-2026-46678","relation":"incomplete-fix","confidence":"high","kind":"lineage","evidence":[{"kind":"text","provenance":"source","relation":"incomplete-fix","quote":"This is an incomplete fix of GHSA-2jrp-274c-jhv3 / CVE-2026-25580, whose remediation did not hold for IPv6-encoded forms of the metadata IPs.","from":"CVE.org","in":"CVE-2026-46678"},{"kind":"osv-related","provenance":"source","id":"GHSA-cqp8-fcvh-x7r3","via":"reference","url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-2jrp-274c-jhv3"},{"kind":"osv-related","provenance":"source","id":"PYSEC-2026-2978","via":"reference","url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-2jrp-274c-jhv3"},{"kind":"osv-related","provenance":"source","id":"PYSEC-2026-2982","via":"reference","url":"https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-2jrp-274c-jhv3"},{"kind":"version-step","provenance":"source","package":"PyPI:pydantic-ai","fromFixed":"1.56.0","toFixed":"1.99.0","daysApart":173},{"kind":"version-step","provenance":"source","package":"PyPI:pydantic-ai-slim","fromFixed":"1.56.0","toFixed":"1.99.0","daysApart":173}]}],"children":[{"from":"CVE-2026-46678","to":"CVE-2026-48782","relation":"incomplete-fix","confidence":"high","kind":"lineage","orderedBy":"description","evidence":[{"kind":"text","provenance":"source","relation":"incomplete-fix","quote":"This is an incomplete fix of GHSA-cqp8-fcvh-x7r3 / CVE-2026-46678 (itself a follow-up to CVE-2026-25580).","from":"CVE.org","in":"CVE-2026-48782"},{"kind":"similar","provenance":"machine","score":0.43,"basis":"same product + CWE + description similarity"}]}],"packageHistory":[{"cve":"CVE-2026-25640","published":"2026-02-06","fixed":"1.51.0","kev":false},{"cve":"CVE-2026-25580","published":"2026-02-06","fixed":"1.56.0","kev":false},{"cve":"CVE-2026-46678","published":"2026-07-29","fixed":"1.99.0","kev":false},{"cve":"CVE-2026-48782","published":"2026-06-16","fixed":"2.0.0b3","kev":false},{"cve":"CVE-2026-54249","published":"2026-07-29","fixed":"2.0.0b6","kev":false},{"cve":"CVE-2026-107294","published":"2026-10-08","fixed":"2.24.0","kev":false}],"package":"PyPI:pydantic-ai"}}