{"id":80658,"date":"2026-06-17T02:19:26","date_gmt":"2026-06-16T22:49:26","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2026-48782-pydantic-ai-ssrf-blocklist-bypass-via-ipv4-compatible-siit-ivi-and-local-nat64-ipv6-addresses-incomplete-fix-of-cve-2026-46678\/"},"modified":"2026-06-17T02:19:26","modified_gmt":"2026-06-16T22:49:26","slug":"cve-2026-48782-pydantic-ai-ssrf-blocklist-bypass-via-ipv4-compatible-siit-ivi-and-local-nat64-ipv6-addresses-incomplete-fix-of-cve-2026-46678","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2026-48782-pydantic-ai-ssrf-blocklist-bypass-via-ipv4-compatible-siit-ivi-and-local-nat64-ipv6-addresses-incomplete-fix-of-cve-2026-46678\/","title":{"rendered":"CVE-2026-48782 &#8211; pydantic-ai: SSRF blocklist bypass via IPv4-compatible, SIIT\/IVI, and local NAT64 IPv6 addresses (incomplete fix of CVE-2026-46678)"},"content":{"rendered":"<p>CVE ID :CVE-2026-48782<\/p>\n<p>  Published : June 16, 2026, 10:49 p.m. | 52\u00a0minutes ago<\/p>\n<p>  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=&#8217;allow-local&#8217; (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.<\/p>\n<p>  Severity: 0.0 | NA<\/p>\n<p>  Visit the link for more details, such as CVSS details, affected products, timeline, and more&#8230;\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CVE ID :CVE-2026-48782 Published : June 16, 2026, 10:49 p.m. | 52\u00a0minutes ago 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 &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-80658","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/80658","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=80658"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/80658\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=80658"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=80658"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=80658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}