{"cve":"CVE-2026-48782","nvd":{"published":"2026-06-17T13:20:43.210","modified":"2026-08-06T18:30:13.047","status":"Analyzed","description":"Pydantic AI is a Python agent framework for building applications and workflows with Generative AI. In versions 1.56.0 through 1.101.0, 2.0.0b1, and 2.0.0b2, the cloud-metadata blocklist could be bypassed by encoding the metadata IP in an IPv6 transition form that the previous fix, CVE-2026-46678, did not decode, exposing cloud IAM short-term credentials. The previous remediation decoded only IPv4-mapped IPv6, 6to4, and the NAT64 well-known prefix, so the metadata guarantee did not hold for the remaining transition forms: IPv4-compatible IPv6 (::a.b.c.d), the NAT64 RFC 8215 local-use prefix (64:ff9b:1::/48), operator-chosen NAT64 prefixes, and ISATAP. The IPv6 wrapper is then delivered to the underlying IPv4 metadata endpoint. This occurs when an application using Pydantic AI opts a URL into force_download='allow-local' (which disables the default block on private/internal IPs) and runs on a network that actually routes the affected IPv6 transition forms: NAT64-configured networks (IPv6-only or dual-stack-with-NAT64 deployments, including some Kubernetes setups) for the NAT64 variants, or networks with an ISATAP tunnel for ISATAP. A standard dual-stack cloud VM or container does not route these forms and is not affected in practice. The IPv4-compatible and Teredo variants are deprecated and addressed as defense-in-depth. This is an incomplete fix of GHSA-cqp8-fcvh-x7r3 / CVE-2026-46678 (itself a follow-up to CVE-2026-25580). This issue has been fixed in version 2.0.0b3.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N","score":6.8},"cwes":["CWE-918"],"references":["https://github.com/pydantic/pydantic-ai/commit/1add06179ba4de259f7ab977620b697b7209f7e4","https://github.com/pydantic/pydantic-ai/pull/5596","https://github.com/pydantic/pydantic-ai/releases/tag/v1.102.0","https://github.com/pydantic/pydantic-ai/security/advisories/GHSA-cg7w-rg45-pc59"],"products":["pydantic:pydantic_ai"],"source":"nvd","synced_at":"2026-10-19T22:39:28.638635428+00:00"},"epss":{"cve":"CVE-2026-48782","score":0.00401,"percentile":0.34343,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-cg7w-rg45-pc59","url":"https://osv.dev/vulnerability/GHSA-cg7w-rg45-pc59","summary":"pydantic-ai: SSRF blocklist bypass via IPv4-compatible, SIIT/IVI, and local NAT64 IPv6 addresses (incomplete fix of CVE-2026-46678)","modified":"2026-07-13T16:43:36.056155706Z","packages":[{"ecosystem":"PyPI","name":"pydantic-ai-slim","purl":"pkg:pypi/pydantic-ai-slim","ranges":[">=1.56.0 <1.102.0"],"fixed":["1.102.0"]},{"ecosystem":"PyPI","name":"pydantic-ai","purl":"pkg:pypi/pydantic-ai","ranges":[">=1.56.0 <1.102.0"],"fixed":["1.102.0"]},{"ecosystem":"PyPI","name":"pydantic-ai","purl":"pkg:pypi/pydantic-ai","ranges":[">=2.0.0b1 <2.0.0b3"],"fixed":["2.0.0b3"]},{"ecosystem":"PyPI","name":"pydantic-ai-slim","purl":"pkg:pypi/pydantic-ai-slim","ranges":[">=2.0.0b1 <2.0.0b3"],"fixed":["2.0.0b3"]}]},{"id":"PYSEC-2026-2977","url":"https://osv.dev/vulnerability/PYSEC-2026-2977","summary":"pydantic-ai: SSRF blocklist bypass via IPv4-compatible, SIIT/IVI, and local NAT64 IPv6 addresses (incomplete fix of CVE-2026-46678)","modified":"2026-07-13T16:43:36.056155706Z","packages":[{"ecosystem":"PyPI","name":"pydantic-ai","purl":"pkg:pypi/pydantic-ai","ranges":[">=1.56.0 <1.102.0",">=2.0.0b1 <2.0.0b3"],"fixed":["1.102.0","2.0.0b3"]}]},{"id":"PYSEC-2026-2981","url":"https://osv.dev/vulnerability/PYSEC-2026-2981","summary":"pydantic-ai: SSRF blocklist bypass via IPv4-compatible, SIIT/IVI, and local NAT64 IPv6 addresses (incomplete fix of CVE-2026-46678)","modified":"2026-07-13T16:43:36.056155706Z","packages":[{"ecosystem":"PyPI","name":"pydantic-ai-slim","purl":"pkg:pypi/pydantic-ai-slim","ranges":[">=1.56.0 <1.102.0",">=2.0.0b1 <2.0.0b3"],"fixed":["1.102.0","2.0.0b3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}